Caliper

Abstract

To accurately measure the thickness dimension of a plate-like part around a hole regardless of its shape or size.SOLUTION: The caliper 10 is capable of measuring the thickness of the plate portion 3 around the hole 2, and includes a cylindrical body 11, a rod 12 inserted into the cylindrical body 11 and configured to be slidable in a longitudinal direction with respect to the cylindrical body 11, a first jaw 13 provided at one end of the cylindrical body 11, and a second jaw 14 provided at a portion of the rod 12 protruding from the cylindrical body 11. A first jaw 13 and a second jaw 14 capable of clamping a plate-shaped part 3 between them, and a distance display part 15 capable of displaying the distance between the first jaw 13 and the second jaw 14 in a digitized state are provided, and a surface 13a of the first jaw 13 and a surface 14a of the second jaw 14 facing each other are formed in shapes different from each other or in areas different from each other.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vernier caliper, and more particularly to a technique for accurately measuring the thickness of a plate-like portion around a hole. [Background technology]

[0002] As is well known, a vernier caliper is commonly used as an instrument for measuring the thickness of a plate-like portion. This instrument (vernier caliper) has long bodies called a main scale and a secondary scale, and a pair of long, thin claws called jaws that extend from the tip of each long body in a direction perpendicular to the longitudinal direction. By moving the long bodies relative to each other along the longitudinal direction, the pair of claws provided at the tip of each long body clamps the portion to be measured, and the distance between the pair of claws in the clamped state can be measured as the thickness of the portion to be measured (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-148505 Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, a vernier caliper can measure the thickness of a target object by clamping the target object between a pair of elongated jaws. Therefore, when measuring the outer periphery of a plate-like object, for example, the target object can be clamped between the pair of jaws without any problems. However, it is difficult to clamp the thickness of a plate-like object (the inner periphery) around a hole in a plate-like object. As described above, the jaws, called "jaws," have a corresponding longitudinal dimension to accommodate target objects of various sizes. Therefore, when the diameter of the hole to be measured is small, the jaws interfere with the periphery of the hole, preventing the hole from passing through. Or, even if the caliper does pass through the hole, it can only clamp the target object at an angle relative to the center line of the hole.

[0005] In view of the above circumstances, the technical problem to be solved in this specification is to accurately measure the thickness dimension of a plate-like portion around a hole regardless of its shape or size. [Means for solving the problem]

[0006] The above-mentioned problem is solved by a caliper according to the present invention. That is, this caliper is capable of measuring the thickness dimension of a plate-like portion around a hole, and is characterized in that it comprises a cylindrical body, a rod-like body inserted into the cylindrical body and configured to be slidable in the longitudinal direction relative to the cylindrical body, a first jaw provided at one end of the cylindrical body, a second jaw provided on a portion of the rod-like body protruding from the cylindrical body and capable of clamping the plate-like portion between itself and the first jaw, and a distance display unit capable of displaying the distance between the first jaw and the second jaw in a numerical form, and that the surfaces of the first jaw and the second jaw facing each other are formed to have different shapes or different areas.

[0007] In the caliper according to the present invention, the shape or size of the first and second jaws, which can clamp the plate-like portion to be measured, is considered, and the surfaces of the first and second jaws facing each other are formed to have different shapes. Alternatively, the surfaces of the first and second jaws are formed to have different areas. When the surfaces of the opposing jaws are formed to have different shapes, for example, the surface of the second jaw located relatively closer to the tip of the caliper can be shaped to be able to pass through the hole, allowing the second jaw to be introduced to the backside of the plate-like portion around the hole without tilting. In this case, by arranging the first jaw, which has a different surface shape from the second jaw, on the front side of the plate-like portion, the first jaw can be reliably abutted against the periphery of the hole. Therefore, after the second jaw has passed through the backside of the hole, for example, by shifting it in a predetermined direction and moving the rod-shaped object in a direction to pull it out of the hole, the plate-like portion around the hole can be clamped between the first and second jaws. All of the operations leading up to clamping can be performed without interfering with the surroundings, so the surface of each jaw can be clamped in a state where it is in contact with the surface of the plate-like part parallel to the surface, thereby making it possible to accurately measure the thickness dimension of the plate-like part.

[0008] Furthermore, by forming the opposing surfaces of each jaw to have different areas, for example, the second jaw, which has a relatively smaller surface area, can be passed through the hole without tilting and introduced to the back side of the plate-like portion, while the first jaw, which has a larger surface area than the second jaw, is positioned on the front side of the plate-like portion, thereby ensuring that the first jaw abuts against the periphery of the hole. Therefore, after the second jaw is passed through the back side of the hole, the rod-shaped object can be pulled out by shifting it in a predetermined direction, thereby clamping the plate-like portion around the hole between the first and second jaws. Furthermore, in this case, all of the clamping operations can be performed without interference with the surroundings, so that the surfaces of each jaw can be clamped parallel to the surface of the plate-like portion, thereby enabling accurate measurement of the thickness of the plate-like portion.

[0009] In the caliper according to the present invention, the second jaw may be attached eccentrically to the rod-shaped body.

[0010] For example, if the second jaw is attached to the rod-shaped body at its center, the area (surface area) in which the second jaw can sandwich the plate-shaped portion between itself and the first jaw is substantially limited to the range from the center of the surface of the second jaw to the outer periphery of the second jaw. In contrast, if the second jaw is attached eccentrically with respect to the rod-shaped body, the area (surface area) in which the second jaw can sandwich the rod-shaped portion between itself and the first jaw can vary along the circumferential direction. That is, by sandwiching the plate-shaped portion between the first jaw and the portion of the surface of the second jaw opposite to the side eccentric from the center (center of gravity) of the rod-shaped body, the sandwiching area with the plate-shaped portion can be maximized. This stabilizes the posture of the caliper (each jaw) when sandwiched, enabling accurate thickness measurements with little variation.

[0011] In the caliper according to the present invention, the rod-shaped body may be configured to be rotatable about its axis relative to the cylindrical body.

[0012] By configuring the rod-shaped body to be rotatable around its axis in this way, for example, after the second jaw has been passed through the hole, the portion of the second jaw that can come into contact with the plate-shaped portion over the largest area can be positioned at the clamping position with the first jaw simply by rotating the rod-shaped body around its axis. This makes it possible to maximize the clamping area of ​​the plate-shaped portion without having to shift the entire caliper in a predetermined direction, thereby stabilizing the posture of each jaw when clamping, thereby enabling accurate plate thickness measurements with little variation.

[0013] In the caliper according to the present invention, the first jaw may be replaceably attached to the cylindrical body, and the second jaw may be replaceably attached to the rod-shaped body.

[0014] By configuring each jaw to be interchangeable in this way, for example, by replacing the second jaw with a jaw of a shape or size that corresponds to the hole defined by the plate-like portion to be measured, i.e., a jaw of a shape or size that can be passed through the target hole, the second jaw can be passed through the hole without tilting or interference, regardless of the shape or size of the hole. Also, by replacing the first jaw with a jaw of a shape or size that abuts against the periphery of the target hole, the first jaw can be reliably abutted against the plate-like portion from the surface side, regardless of the shape or size of the hole. [Effects of the Invention]

[0015] As described above, the caliper according to the present invention makes it possible to accurately measure the thickness of a plate-like portion around a hole regardless of its shape or size. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a front view of a vernier caliper according to an embodiment of the present invention. [Figure 2] FIG. 2 is a view of the caliper shown in FIG. 1 as seen from the tip end side in the longitudinal direction. [Figure 3] FIG. 2 is a front view illustrating a state in which a second jaw is inserted into a hole, illustrating an example of a method for measuring the thickness dimension of a plate-like portion using the caliper shown in FIG. 1. [Figure 4] FIG. 2 is a front view illustrating an example of a method for measuring the thickness dimension of a plate-like portion using the caliper shown in FIG. 1, showing a state in which a rod-like body is rotated around its axis. [Figure 5] FIG. 2 is a diagram for explaining an example of a method for measuring the thickness dimension of a plate-like portion using the caliper shown in FIG. 1, and is a front view showing a state in which the second jaw is brought close to the first jaw to clamp the plate-like portion. [Figure 6] FIG. 10 is a view of a caliper according to another embodiment of the present invention, as viewed from the tip end side in the longitudinal direction. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, the details of a caliper according to one embodiment of the present invention will be described with reference to the drawings.

[0018] FIG. 1 is a front view of a caliper 10 according to one embodiment of the present invention, and FIG. 2 is a view of the caliper 10 shown in FIG. 1 as seen from the longitudinal tip side. This caliper 10 is capable of measuring the thickness dimension of a plate-like portion 3 around a hole 2 formed in a plate-like body 1 having a closed structure, as shown in FIG. 3, for example, and includes a cylindrical body 11, a rod-like body 12, a first jaw 13, a second jaw 14, and a distance display unit 15. In this embodiment, the caliper 10 further includes a gripping portion 16 and a fixing nut 17. Each element will be described in detail below.

[0019] The cylindrical body 11 allows the rod-shaped body 12 to be inserted therethrough, and has a first jaw 13 at one end. In this embodiment, the longitudinal dimension of the cylindrical body 11 is set to a predetermined size so that both longitudinal sides of the rod-shaped body 12 protrude (expose) from the cylindrical body 11.

[0020] The rod-shaped body 12 is configured to be slidable in the longitudinal direction relative to the cylindrical body 11 while inserted through the cylindrical body 11. A second jaw 14 is attached to a portion of the rod-shaped body 12 that protrudes (exposed) from the cylindrical body 11 on one side in the longitudinal direction. Meanwhile, a gripping portion 16 is attached to the other end of the rod-shaped body 12 in the longitudinal direction from the cylindrical body 11, allowing the rod-shaped body 12, and therefore the second jaw 14, which will be described later, to rotate about its axis and slide along the longitudinal direction.

[0021] In this embodiment, a fixing nut 17 is disposed on the outer periphery of the portion of the rod-shaped body 12 that protrudes from the cylindrical body 11 to the other longitudinal side (the side opposite to the attachment side of the second jaw 14) (see FIG. 1). In this case, a male thread portion (not shown) is formed in the region of the outer periphery of the rod-shaped body 12 where the fixing nut 17 is provided, and this male thread portion is threadedly engaged with a female thread portion provided on the inner periphery of the fixing nut 17. Therefore, the fixing nut 17 is movable in the longitudinal direction relative to the rod-shaped body 12 as it is rotated (operated) around its axis.

[0022] The first jaw 13 is attached to one longitudinal end of the cylindrical body 11, and in this embodiment, the first jaw 13 is plate-shaped. Furthermore, a surface 13a of the first jaw 13 facing the second jaw 14 extends perpendicular to the longitudinal direction of the cylindrical body 11 and is circular. A through hole 13b is formed in the first jaw 13. For example, a female threaded portion (not shown) is formed on the inner periphery of the through hole 13b, and a male threaded portion (not shown) is formed on the outer periphery of one longitudinal end of the cylindrical body 11, thereby removably attaching the first jaw 13 to the cylindrical body 11. Note that the above-described attachment configuration is merely exemplary. For example, although not shown, the first jaw 13 may be removably attached to the cylindrical body 11 using a countersunk screw or bolt. In short, the attachment configuration of the first jaw 13 to the cylindrical body 11 is arbitrary. Similarly, any desired attachment form can be applied to the attachment form of the second jaw 14 to the rod-shaped body 12, which will be described later.

[0023] In this embodiment, a through hole 13b is formed in the first jaw 13 so that the center C1 of the first jaw 13 is positioned at a position radially eccentric by a predetermined distance from the center C0 of the rod-shaped body 12, which substantially coincides with the center of the cylindrical body 11, and the cylindrical body 11 is attached to the inner circumference of this through hole 13b.

[0024] The second jaw 14 is attached to one longitudinal end of the rod-shaped body 12, and in this embodiment, the second jaw 14 is plate-shaped. The surface 14a of the second jaw 14, which faces the first jaw 13, extends in a direction perpendicular to the longitudinal direction of the rod-shaped body 12 and is circular. Therefore, in this case, the surfaces 13a of the first jaw 13 and 14a of the second jaw 14, which face each other, are always parallel to each other. In this embodiment, a through hole 14b is formed in the second jaw 14 so that the center C0 of the rod-shaped body 12 is positioned at a predetermined radial distance eccentric from the center C2 of the second jaw 14. For example, a female thread (not shown) is formed on the inner periphery of the through hole 14b, and a male thread (not shown) is formed on the outer periphery of one longitudinal end of the rod-shaped body 12. This allows the second jaw 14 to be detachably attached in an eccentric state relative to the rod-shaped body 12. 2 illustrates an example in which the center C1 of the first jaw 13 and the center C2 of the second jaw 14 coincide with each other, but of course the eccentric directions of the centers C1 and C2 relative to the center C0 of the rod-shaped body 12 may be different. Alternatively, the eccentric distances of the centers C1 and C2 relative to the center C0 may be different.

[0025] Here, when comparing the surface 13a of the first jaw 13 and the surface 14a of the second jaw 14, which face each other, in this embodiment, the area of ​​the surface 14a of the second jaw 14 is set smaller than the area of ​​the surface 13a of the first jaw 13. Also, in this case, when the first jaw 13 and the second jaw 14 are viewed from the tip side in the longitudinal direction of the caliper 10, the surface 14a of the second jaw 14 entirely overlaps with the surface 13a of the first jaw 13 (see FIG. 2).

[0026] The distance display unit 15 is capable of displaying the distance between the surface 13a of the first jaw 13 and the surface 14a of the second jaw 14, which face each other, in a numerical form, and is configured, for example, by providing a main scale on one of the cylindrical body 11 and the rod-shaped body 12, and a vernier scale on the other of the cylindrical body 11 and the rod-shaped body 12. Note that this configuration of the distance display unit 15 is merely an example, and it is also possible to apply any general configuration that can display the distance between the jaws 13, 14 in a numerical form, including other scales for calipers, such as a dial scale or a digital scale.

[0027] Next, an example of a method for measuring the thickness dimension of the plate-like portion 3 using the caliper 10 having the above-described configuration will be described mainly with reference to FIGS.

[0028] First, the caliper 10 is positioned so that the penetration direction of the hole 2 in the closed-shaped (box-shaped) plate-like body 1 and the longitudinal direction of the rod-like body 12 are aligned (parallel) and so that the hole 2 and the second jaw 14 are directly opposite each other. Then, the caliper 10 is moved toward the hole 2. Here, the second jaw 14 located at the front end of the movement direction of the caliper 10 has a shape and outer diameter that allows it to pass through the hole 2 (in other words, the second jaw 14 is attached so that it has a shape and outer diameter that allows it to pass through the hole 2). Therefore, by moving the caliper 10 toward the hole 2, the second jaw 14 can be passed through the hole 2 and introduced onto the back side of the plate-like portion 3 located around the hole 2 (see FIG. 3 ).

[0029] In addition, at this time, by setting the shape and dimensions (circumscribed circle diameter) of the surface 13a of the first jaw 13 so that the circumscribed circle diameter of the surface 13a of the first jaw 13 is larger than the inscribed circle diameter of the hole 2, after the second jaw 14 has been passed through the hole 2, the vernier caliper 10 can be continued to move so that the surface 13a of the first jaw 13 can be brought into contact with the surface (front surface) of the plate-like portion 3 around the hole 2 (see Figure 3).

[0030] In this way, second jaw 14 is passed through hole 2, and first jaw 13 is brought into contact with plate-like portion 3, which is the portion to be measured. Then, gripping portion 16 is rotated around the central axis of rod-like body 12 (a virtual axis passing through center C0), thereby axially rotating second jaw 14 (see FIG. 4). At this time, since second jaw 14 is attached eccentrically with respect to rod-like body 12 (see FIG. 2), the axial rotation described above causes the region on the side that is relatively far from center C0 of rod-like body 12, which is the center of axial rotation, to face plate-like portion 3 (see FIG. 4).

[0031] From this state, by lifting up the rod-shaped body 12 and bringing the second jaw 14 attached to the tip thereof close to the first jaw 13, the plate-shaped portion 3 around the hole 2 is sandwiched between the first jaw 13 and the second jaw 14 (see FIG. 5). Therefore, by measuring the distance between the surface 13a of the first jaw 13 and the surface 14a of the second jaw 14 in this state with the distance display unit 15, it is possible to measure the thickness dimension of the plate-shaped portion 3 sandwiched between these surfaces 13a, 14a.

[0032] In addition, when a fixing nut 17 is provided on the outer periphery of the rod-shaped body 12 as in this embodiment, the plate-shaped portion 3 to be measured may be clamped between the first jaw 13 and the second jaw 14, and the fixing nut 17 may be rotated about its axis to move toward the second jaw 14, so that the plate-shaped portion 3 and the first jaw 13, and the cylindrical body 11, the fixing nut 17, and the second jaw 14 are clamped and fixed together (the state shown in FIG. 5 ). In this way, the state in which the plate-shaped portion 3 is clamped between the first jaw 13 and the second jaw 14 can be maintained. Therefore, it becomes possible to accurately and easily measure the distance between the first jaw 13 and the second jaw 14, and therefore the thickness dimension of the plate-shaped portion 3.

[0033] As described above, with the caliper 10 according to this embodiment, the second jaw 14, which is located relatively closer to the tip of the caliper 10, can be passed through the hole 2, while the first jaw 13, which is located closer to the base end of the caliper 10 than the second jaw 14, can be brought into contact with the plate-like portion 3 around the hole 2. Therefore, from this state, the entire caliper 10 can be shifted in a direction along the surfaces 13a, 14a of the jaws 13, 14 and then the second jaw 14 can be lifted up, or, as in this embodiment, the second jaw 14 can be rotated around the central axis of the rod-shaped body 12 and then the second jaw 14 can be lifted up, thereby clamping the plate-like portion 3 around the hole 2 between the first jaw 13 and the second jaw 14. Furthermore, according to the caliper 10 of this embodiment, for the reasons described above, the surface 13a of the first jaw 13 and the surface 14a of the second jaw 14 both extend in a direction perpendicular to the longitudinal direction of the caliper 10 (cylindrical body 11, rod-shaped body 12), and the plate-shaped portion 3 can be clamped with the penetration direction of the hole 2 (i.e., the thickness direction of the plate-shaped portion 3) aligned with the longitudinal direction of the caliper 10. Therefore, the distance between the jaws 13, 14 can be accurately read from the distance display unit 15 as the thickness dimension of the plate-shaped portion 3.

[0034] Furthermore, by adopting a structure in which the first jaw 13 is detachably attached to the cylindrical body 11 and the second jaw 14 is detachably attached to the rod-shaped body 12, as in the caliper 10 according to this embodiment, it is possible to easily measure the thickness dimensions of plate-like portions 3 around holes 2 of various shapes and dimensions simply by replacing the first jaw 13 and second jaw 14 with those of appropriate shapes and dimensions according to the shape and dimensions of the hole 2. Therefore, the caliper 10 according to this embodiment can be made more versatile for use in measuring portions.

[0035] Although one embodiment of the present invention has been described above, the caliper according to the present invention can also have configurations other than those described above within the scope of the gist of the invention.

[0036] For example, in the above embodiment, the combination of the first jaw 13 and the second jaw 14 is exemplified as a combination in which the area of ​​the surface 14a of the second jaw 14 is smaller than the area of ​​the surface 13a of the first jaw 13, but of course the caliper according to the present invention is not limited to the above-exemplified form. Figure 6 shows a view of a caliper 20 according to one example (another embodiment of the present invention) as seen from one end side (tip side) in the longitudinal direction. As shown in this figure, in the caliper 20 according to this embodiment, the surface 24a of the second jaw 24 is in a perfect circular shape, while the surface 23a of the first jaw 23 is in a flattened circular shape (slot-shaped). In the caliper 20 having the first jaw 23 and the second jaw 24 in such a combination that the surfaces 23a, 24a have different shapes, even if the area of ​​the surface 23a of the first jaw 23 is equal to or smaller than the area of ​​the surface 24a of the second jaw 24 as shown in the figure, the second jaw 24 can be passed through the hole 2 having a perfectly circular shape as shown in FIG. 3, and the first jaw 23 can be brought into contact with the plate-like portion 3 around the hole 2 to clamp the plate-like portion 3 between the first jaw 23 and the second jaw 24. When the surface shapes of the jaws are different from each other as described above, it is preferable to form each surface so that the circularity of the surface shape of the jaw located at the tip end of the caliper (the second jaw in this specification) is smaller than the circularity of the surface shape of the jaw located at the base end (the first jaw in this specification). Furthermore, the above-described effects can be achieved as long as the shape and dimensions of the surfaces of the jaws are set so that the circumscribed circle diameter of the surfaces of the first jaws facing each other is larger than the circumscribed circle diameter of the surfaces of the second jaws.

[0037] Alternatively, although not shown, the above-described effects can also be achieved with a caliper having a first jaw and a second jaw whose opposing surfaces have the same area and shape. For example, although not shown, in the case of a caliper having a first jaw and a second jaw whose opposing surfaces both form a polygonal shape corresponding to the hole 2 and have the same area, by rotating the first jaw by a predetermined angle around the cylindrical body relative to the second jaw, when the second jaw is inserted through the hole 2, the vertex of the polygonal peripheral portion of the surface of the first jaw is positioned directly opposite the plate-like portion 3 surrounding the hole 2. Therefore, even after the second jaw has been inserted through the hole 2, the entire caliper can be continued to be moved in the direction of passage through the hole 2, thereby making it possible to bring the first jaw into contact with the plate-like portion 3 surrounding the hole 2.

[0038] In addition, in the above embodiment, the case where the second jaw 14 is attached in an eccentric state with respect to the rod-shaped body 12 has been exemplified, but of course, this is not limited to this. As long as a sufficient clamping area (contact area) can be secured between the second jaw 14 and the first jaw 13, the center (center of gravity) C2 of the second jaw 14 may be aligned with the center C0 of the rod-shaped body 12. Similarly, the center C1 of the first jaw 13 may be aligned with the center C0 of the rod-shaped body 12.

[0039] Furthermore, in the above explanation, an example was given in which the plate-like portion 3 around the hole 2 in the plate-like body 1 having a closed shape was used as the object for measuring the thickness dimension, but of course this is not limited to this. The caliper according to the present invention can of course be applied to cases in which the object for measuring the thickness dimension is a plate-like portion around a hole in an object where it is difficult to access the back side of the hole 2, or to cases in which the object for measuring the thickness dimension is a portion that can be measured even with a conventional caliper, such as when the outer periphery of a plate-like body in an open state is used as the object for measuring the thickness dimension. [Explanation of symbols]

[0040] 1 Plate-shaped body 2 holes 3 Plate-shaped parts 10,20 Vernier calipers 11 Cylindrical body 12 Rod-shaped body 13,23 First Joe 13a,23a surface 14,24 Second Joe 14a,24a surface 15 Distance display section 16 Gripping part 17 Fixing nut C0 center (rod) C1 Center (first jaw) C2 Center (Second jaw)

Claims

[Claim 1] A vernier caliper capable of measuring the thickness of a plate-like portion around a hole, A cylindrical body; a rod-shaped body that is inserted into the cylindrical body and configured to be slidable in a longitudinal direction relative to the cylindrical body; a first jaw provided at one end of the cylindrical body; a second jaw provided on a portion of the rod-shaped body protruding from the cylindrical body and capable of clamping the plate-shaped portion between itself and the first jaw; a distance display unit capable of displaying the distance between the first jaw and the second jaw in a numerical form, A vernier caliper, wherein the surfaces of the first jaw and the second jaw facing each other are formed to have different shapes or areas.

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