JP3045593U - Inner micrometer - Google Patents

Abstract

(57) [Problem] To provide an inner micrometer capable of easily and accurately measuring the inner diameter of a tubular article having a projection at the center or the hole diameter of a workpiece at the time of boring with a lathe. SOLUTION: Along a straight line connecting a U-shaped grip portion (2) and a pair of opposing top portions (3) of the grip portion (2), it protrudes outside one of the top portions (3). An inner micrometer (1) comprising a micrometer part (4) provided and a rod part (5) protruding outside the other top part (3).

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to an inner micrometer for accurately measuring the inner diameter of a tubular object having a projection at the center or the hole diameter of a workpiece during boring by a lathe.

[0002]

[Prior art]

 Conventionally, a rod-shaped inner micrometer is known as an instrument for accurately measuring a hole diameter, a groove width, and the like. As shown in FIG. 2, this is a rod-shaped object including a grip portion 15, a micrometer portion 13, and a rod portion 14. When measuring the inner diameter of the tubular workpiece 8, the grip portion 15 is gripped with one hand. Then, the distal anvil 13a of the micrometer section 13 and the distal anvil 14a of the rod section 14 are brought into contact with the diametric inner surface 11 of the tubular workpiece 8, and the micrometer section 13 is rotated and adjusted with the other hand. Read the scale. The rod-shaped inner micrometer has a gripping part that can be attached to and detached from the micrometer part and the rod part, and can be used to measure large-diameter tubular objects by adding several gripping parts. Some are referred to as inner micrometers.

[0003]

[Problems to be solved by the invention]

 However, when measuring the inner diameter of a tubular object having a projection at the center or the hole diameter of a workpiece at the time of boring with a lathe, the conventional micrometer requires the projection at the center or a tailing jig of a lathe. Can not be used in the way. In such a case, usually, as shown in FIG. 3, the bore diameter of the workpiece 8 gripped by the chuck 17 of the lathe and the tailstock 9 is measured using the inner path 16. However, this method is liable to cause a measurement error, requires skill and labor, and it has been difficult to perform a precise measurement. Therefore, an object of the present invention is to provide an inner micrometer capable of easily and accurately measuring the inner diameter of a tubular object having a projection at the center or the hole diameter of a workpiece during boring with a lathe.

[0004]

[Means for Solving the Problems]

 In order to achieve the above object, according to the present invention, the present invention is characterized in that a grip portion having a relief at a central portion and a straight extension line connecting a pair of opposed top portions of the grip portion are provided. The problem is solved by an inner micrometer having a micrometer portion protruding outside one of the top portions and a rod portion protruding outside the other top portion. According to the second aspect of the present invention, an inner micrometer in which the grip, the micrometer, and the rod can be detachably connected to each other. In the invention of claim 3, the grip portion may be an inner micrometer having any one of a U shape, a substantially U shape, and a crescent shape. According to the invention of claim 4, an inner micrometer having an opening in the grip portion can be provided.

[0005]

[Embodiment of the invention]

 An embodiment of the inner micrometer of the present invention will be described with reference to FIG. In FIG. 1, an inner micrometer 1 is formed along a straight line extending from a rigid frame having a relief at a central portion thereof, for example, a U-shaped grip portion 2 and a pair of opposed U-shaped top portions 3 and 3. It comprises a micrometer section 4 and a rod section 5 projecting outside the tops 3 and 3. The grip portion 2 is connected to the micrometer portion 4 and the rod portion 5 by providing holes 6 and 6 formed outside the top portions 3 and 3 of the grip portion 2 and provided in the micrometer portion 4 and the rod portion 5. The rod-shaped projections 7, 7 are engaged with each other, but the method is not limited to this method. In addition, by forming the connecting part of the grip part and the micrometer part and the rod part so as to be detachable, the grip part can be replaced with a U-shaped part with a different top-to-top distance and connected to form a hole of different size. The inner diameter of an object or the like can be measured. In this case, only the U-shaped grip portion is prepared using the micrometer portion and the rod portion of a commercially available refillable inner micrometer, and the U-shaped grip portion is provided outside the top portion of the grip portion in accordance with the mating projection of the micrometer portion and the rod portion. It can be used by drilling and mating the three. The grip portion 2 may have any shape as long as it has a relief at the center, and may be U-shaped, substantially U-shaped, crescent-shaped, or the like. When the opening 12 is formed around the bottom 10 of the grip 2, the weight of the inner micrometer can be reduced.

Next, the method of using the inner micrometer 1 will be described again with reference to FIG. FIG. 1 shows an example of measuring the hole diameter of a workpiece 8 at the time of boring, and shows a cross section of a tailing jig 9 of a lathe at the center of the round bar-shaped workpiece 8. The U-shaped bottom 10 of the grip portion 2 of the inner micrometer 1 is gripped with one hand, and the tail surface jig 9 is positioned between the U-shaped tops 3 and 3 so as to bore the inner surface 11 of the workpiece 8. When the anvils 4a and 5a at the tips of the micrometer section 4 and the rod section 5 are oriented vertically, and the micrometer section 4 is rotated and adjusted with the other hand, and the tip comes into contact with the inner side surface 11. Read the scale of.

[0007]

【Example】

 A grip portion 2 having a dimension between the outer sides of the two U-shaped tops 3 and 3 of 200 mm, a micrometer portion 4 having a length of 150 mm and a movable range (measurement range) of ± 10 mm, and a rod portion having a length of 150 mm 5 were combined to produce an inner micrometer 1 with a total length of 500 mm. Then, the workpiece 8 was cut by a lathe so that the hole diameter of the workpiece 8 became 500 mm, and accurate measurement in units of microns could be easily performed using the inner micrometer 1.

[0008]

[Effect of the invention]

 In the inner micrometer of the present invention, the grip has a shape with a relief, so when measuring the inner diameter of a tubular object with a projection at the center or the hole diameter of the workpiece at the time of boring with a lathe, etc. Precise measurement can be easily performed without the center projection or tailstock of the lathe obstructing. Also, in the inner micrometer of the present invention, by making the connection between the grip part, the micrometer part and the rod part detachable, when measuring the inside diameter of various sizes, the grip part of the corresponding size can be used. Since it is sufficient to select and combine, the width of the measurement range can be widened at low cost.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of an inner micrometer according to the present invention and a partial cross-sectional view showing a measurement state by the same.

FIG. 2 is a partial cross-sectional view of a front view showing a conventional inner micrometer and a diagram showing a measurement state using the same.

FIG. 3 is a partial cross-sectional view showing a conventional measurement state at the time of boring with a lathe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inner micrometer 2,15 Grip part 3 Top part 4,13 Micrometer part 4a, 5a, 13a, 14a Anvil 5,14 Rod part 6 Hole 7 Bar-shaped projection 8 Work 9 Tailstock jig 10 Bottom part 11 Inner side surface 12 Opening Part 16 Inside pass 17 Chuck

Claims (4)

[Utility model registration claims] 1. A grip portion having a relief at a central portion, and a micrometer portion protruding outside one of the top portions along an extension of a straight line connecting a pair of opposed top portions of the grip portion. And a rod protruding outside the other top. 2. The inner micrometer according to claim 1, wherein a connection between the grip portion, the micrometer portion and the rod portion is detachable. 3. The inner micrometer according to claim 1, wherein the grip portion has one of a U shape, a substantially U shape, and a crescent shape. 4. The inner micrometer according to claim 1, wherein an opening is formed in the grip portion.