JP2001165791A - Device, method, and tool for measuring axial force of screwed body and evaluation system of screwed body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for measuring the axial force of a screwed body that can measure axial force while internal and external threads are actually screwed each other. SOLUTION: This measuring device is used to measure clamping force when an external thread Y and an internal thread X that are arranged opposingly are screwed relatively by at least two arrangement means that retain the external thread Y or the internal thread X at one end and are fixed to a body A that is essentially the same. The measuring device is provided with a seat surface torque load cell 2 having a top plate 1 where the seat surface of the external thread Y touches and a fixation part for fixing to the side of a body A, an internal thread torque load cell 4 for gear-locking the rotary direction of the internal thread X that is screwed to the external thread Y of the sear surface torque load cell 2, an axial load cell 3 for converting distortion being generated by the clamping of the external thread Y or the internal thread X being arranged opposingly, and a conversion part B for performing the conversion processing of the distortion that is obtained by the axial force load cell 3 as the axial force of the screwed body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for measuring a torque and an axial force, that is, an axial force when a male screw such as a bolt and a female screw such as a nut are screwed together.

[0002]

2. Description of the Related Art As a conventional technique relating to measurement of an axial fastening force (hereinafter referred to as "axial force") when a male screw such as a bolt and a female screw such as a nut are screwed, there is known a technique such as a bolt or a nut. It is generally known that the measurement is separately performed by each measuring instrument. That is, in the conventional measuring device for measuring the axial force of a screw, the male screw and the female screw are each measured by being screwed into a measuring instrument.

[0003]

However, it has not been possible to evaluate the axial force of a screwed body generated when a male screw and a female screw are actually screwed together.

Accordingly, the present invention has been made in view of the above-mentioned problems which have not been solved by the prior art, and there is provided a threaded body which can measure an axial force in a state where a male screw and a female screw are actually screwed. It is an object of the present invention to provide an axial force measuring device, an axial force measuring method thereof, an axial force measuring jig thereof, and an evaluation system of a screw body.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, a first aspect of the present invention is to provide a device comprising two or more arranging means which hold a male screw or a female screw at one end and are fixed to substantially the same body at the other end. A device for measuring an axial force when the arranged male screw and female screw are relatively screwed with each other, and a contact portion for contacting a bearing surface of one screw and a fixing portion for fixing to a main body side. A first arranging means having a first arranging means, a second arranging means for locking and holding the rotation direction of the other screw screwed with the screw of the first arranging means, Or an axial force detecting means for converting a distortion generated by fastening of the internal thread into an electric signal, and a conversion processing means for converting the electric signal generated by the axial force detecting means as an axial force. It is an axial force measuring device for a screw body.

According to a second aspect of the present invention, in the axial force measuring device for a screw body according to the first aspect, the axial force detecting means includes:
One end is disposed between the first arranging means and the second arranging means, and a first abutting portion which abuts on a seat surface of either a male screw or a female screw; A cylindrical member formed in a thin cylindrical shape having a second contact portion fixed integrally, and a strain gauge attached to a cylindrical portion of the cylindrical member to detect distortion of the cylindrical portion. It is characterized by having.

According to a third aspect of the present invention, in the axial force measuring device for a threaded body according to the first aspect, the second contact portion is not fixed to the main body side and the first arranging means is connected to the second arranging means. And is fastened by the above-mentioned screw body to cause distortion in the shrinking direction at the cylindrical portion.

According to a fourth aspect of the present invention, there is provided the axial force measuring device for a threaded body according to any one of the first to third aspects, wherein a main body is provided on a side of the first arranging means which comes into contact with a seat surface of the screw. It has a bearing opposing part which contacts with a side via a bearing, and the above-mentioned contact part can be twisted with respect to the above-mentioned main part.

According to a fifth aspect of the present invention, in the axial force measuring device for a screwed body according to the fourth aspect, an axial line of the screwed body is provided on the other axial side of the first arranging means from the bearing facing portion. A fixed opposing portion fixed to the main body at a position close to the main body.

According to a sixth aspect of the present invention, in the apparatus for measuring axial force of a screwed body according to any one of the first to fifth aspects, the first arranging means includes a cylindrical portion along an axis of the screwed body. One end of the cylindrical portion is fixed substantially integrally with the bearing opposing portion, and the other end of the cylindrical portion is fixed substantially integrally with the main body.

According to a seventh aspect of the present invention, in the apparatus for measuring axial force of a screw body according to any one of the first to sixth aspects, the thin cylinder of the axial force detecting means is provided in the cylindrical portion of the first arranging means. The second arrangement means is provided concentrically on the axis of the screw body in the thin cylindrical part of the axial force detection means.

According to an eighth aspect of the present invention, in the axial force measuring device for a threaded body according to any one of the first to seventh aspects, the other end of the second arranging means in the axial direction is the main body in the rotational direction. It is characterized by being fixed substantially integrally with the side.

According to a ninth aspect of the present invention, in the apparatus for measuring an axial force of a screwed body according to any one of the first to eighth aspects, the second arranging means is movable along an axis of the screwed body. It is characterized by being installed.

[0014] The invention of claim 10 is the invention of claims 1 to 9
In the axial force measuring device for a threaded body according to any one of the above, a holding means for engaging the screw to be arranged is provided on the side of the second arrangement means for engaging the screw.

According to an eleventh aspect of the present invention, in the apparatus for measuring an axial force of a screw body according to the tenth aspect, the holding means comprises:
A projection is provided at one end of the second arranging means, and the projection can be engaged with a notch formed in advance on the screw.

According to a twelfth aspect of the present invention, in the apparatus for measuring the axial force of a screwed body according to the tenth aspect, the holding means comprises:
It is characterized in that a fitting structure substantially identical to the outer diameter shape of the screw is provided.

Further, the invention of claim 13 is the invention of claims 1-1
2. The axial force measuring device for a screwed body according to any one of 2), wherein the second arranging means is provided with a shaft escape hole so as not to interfere with a shaft portion of a male screw screwed into the held female screw. And

Further, the invention of claim 14 is the invention of claims 1-1
3. The axial force measuring device for a screw body according to any one of 3, wherein a detachable mechanism is provided between the main body side on which the first arranging means is installed and the second arranging means. And

According to a fifteenth aspect of the present invention, in the method for measuring an axial force of a screw body for measuring a fastening force when a male screw and a female screw are relatively screwed, one of the pair of screws is placed in a first arrangement. While being arranged rotatable with respect to the main body to the means,
The other is fixedly arranged on the second arrangement means with respect to the main body, and a compressive force or a tensile force is applied to the axial force detection means by screwing the pair of screws together, thereby reducing the distortion of the axial force detection means. The axial force of the threaded body is converted into an axial force by the screw of (1).

According to a sixteenth aspect of the present invention, in the method for measuring the axial force of the threaded body according to the fifteenth aspect, the axial force detecting means includes an external thread or an internal thread provided at one end of the thin cylindrical member. And the other end is fixed substantially integrally with the main body side, and the strain at the cylindrical portion is detected by a strain gauge attached to the cylindrical portion of the cylindrical member. .

According to a seventeenth aspect of the present invention, in the method for measuring an axial force of a screwed body according to the sixteenth aspect, the axial force detecting means is tightened by the screwed body to generate distortion in a contraction direction. I have.

Further, the invention of claim 18 is the invention of claims 15 to
17. The method for measuring an axial force of a screw body according to any one of 17
The first arranging means is characterized in that distortion is caused by a torsional moment.

Further, the invention of claim 19 provides the invention according to claims 15 to
18. The method for measuring the axial force of a screwed body according to any one of claims 18,
The second arrangement means is characterized in that the other end in the axial direction is fixed substantially integrally with the main body side in the rotation direction.

Further, the invention of claim 20 provides the invention according to claims 15 to
19. The method for measuring an axial force of a screwed body according to any one of 19,
It is characterized in that the second arranging means is movably installed along the axis of the screw body.

Further, the invention of claim 21 is the invention of claims 15 to
20. The method for measuring an axial force of a screw body according to any one of 20.
A screw arranged on the side of the second arrangement means for engaging the screw engages with the side of the second arrangement means for engaging the screw.

Further, the invention of claim 22 provides the invention according to claims 15 to
21. The method for measuring an axial force of a screwed body according to any one of
The second arranging means is characterized in that the shaft portion of the male screw screwed into the held female screw escapes the shaft portion so as not to interfere.

Further, the invention of claim 23 provides the invention according to claims 15 to
22. The method for measuring an axial force of a screw body according to any one of 22.
It is characterized in that the main body side on which the first arrangement means is installed and the second arrangement means are detachable.

According to a twenty-fourth aspect of the present invention, a male screw and a female screw are opposed to each other by two or more arranging means which hold a male screw or a female screw at one end and are fixed to substantially the same main body at the other end. A jig for measuring the fastening force at the time of screwing, the first arrangement means having a contact portion for contact with the bearing surface of one screw and a fixing portion for fixing to the body side, A second arranging means that locks and holds the rotation direction of the other screw screwed with the screw of the first arranging means,
A jig for measuring axial force of a screwed body, comprising: an axial force detecting means for converting distortion into an electric signal by fastening the male screw or female screw disposed opposite to each other.

According to a twenty-fifth aspect of the present invention, in the jig for measuring the axial force of the screw body according to the twenty-fourth aspect, the axial force detecting means has one end connected to the first arranging means and the second arranging means. A thin wall having a first abutting portion disposed between the abutment surfaces of either the male screw or the female screw and a second abutting portion fixed at the other end and substantially integrally with the main body side It is characterized by being constituted by a cylindrical member formed in a simple cylindrical shape, and this cylindrical portion is distorted by screwing of a male screw and a female screw.

According to a twenty-sixth aspect of the present invention, in the jig for measuring the axial force of the screw body according to the twenty-fifth aspect, the axial force detecting means includes a strain gauge for detecting distortion of a cylindrical portion of the cylindrical member. It is characterized by having.

According to a twenty-seventh aspect of the present invention, in the jig for measuring an axial force of a screw body according to the twenty-fourth aspect, the second arranging means is detachable from the main body. .

According to a twenty-eighth aspect of the present invention, in the jig for measuring the axial force of the screwed body according to the twenty-fourth aspect, the second arranging means has means movable along the axis of the screwed body. Features.

According to a twenty-ninth aspect of the present invention, in the jig for measuring the axial force of the screw body according to the twenty-fourth aspect, the second arranging means has a projection shape for fitting into a recess provided in advance in the screw. , The rotation direction of the screw is locked.

According to a thirtieth aspect of the present invention, in the jig for measuring an axial force of a screw body according to the twenty-fourth aspect, the second arranging means has a fitting structure that is substantially the same as the outer diameter of the screw. The rotation direction of the screw is locked by the above.

According to a thirty-first aspect of the present invention, in a screwed body evaluation system for measuring and evaluating a fastening force when a male screw and a female screw are relatively screwed, one of the pair of screws is rotatable. A first disposing means for disposing, a second disposing means for disposing the other fixedly, and a shaft interposed between the pair of screws and for applying a compressive force or a tensile force by screwing the pair of screws together. Force detecting means, conversion processing means for converting distortion of the axial force detecting means into axial force by the pair of screws, and design evaluation means for performing a design evaluation of the screw based on the conversion processing result. A threaded body evaluation system for determining the use of a screw based on a design evaluation result.

[0036]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of the axial force measuring device of the first embodiment, and FIG. 2 is a cross-sectional view showing the entire configuration of the measuring device. The outline of this overall configuration is given by the axis Z
A top plate 1 for holding a male screw Y such as a bolt at one end in the direction, a seat torque load cell 2 which is a seat torque detecting means for generating distortion by a seat torque of the arranged male screw Y, a male screw Y and a female screw X , A female screw torque load cell 4 that holds a female screw X screwed in opposition to the arranged male screw Y and generates a distortion by this torque, and a seat torque load cell. 2, a strain gauge H3 attached to the internal thread torque load cell 4 for detecting the strain, a strain gauge H3 attached to the female screw torque load cell 4, and an axial load cell 3.
A strain gauge H2 that is attached to and detects the strain;
A pedestal 5 for mounting each of the above members as a substantially integrated unit
And a main body A for fixing the pedestal 5. Here, the case where the external thread Y is set on the top plate 1 and the internal thread X is set on the internal thread torque load cell 4 for measurement will be described. In the drawings, reference symbol W denotes a member to be fastened, such as a washer, and reference symbol T denotes a hexagon socket set screw.

The seat torque load cell 2 against the pedestal 5
Is fixed from above via a ball bearing 6 such that the cylindrical portion 2a is accommodated in the pedestal 5. The axial load cell 3 is inserted into the cylindrical portion 2a of the seat torque load cell 2 disposed inside the pedestal 5 and the thin cylindrical portion 3a is fixed to the pedestal 5 from below. The female screw torque load cell 4 is inserted into the thin cylindrical portion 3a of the axial force load cell 3, and the rotation direction is fixed via the intermediate block 7, the end block 11, and the like into which the guide sleeve 10 is press-fitted. That is, with respect to the pedestal 5, the members of the top plate 1, the bearing surface torque load cell 2, the axial load cell 3, and the female screw load cell 4 are concentrically arranged on the axis Z where the male screw Y and the female screw X are screwed. To save space. Strain gauge H1 attached to seat torque load cell 2 as first detection means, strain gauge H3 attached to female screw torque load cell 4 as second detection means, and strain gauge attached to axial load cell 3 as axial force detection means H2 is connected to a conversion unit B, which is a conversion processing unit.

FIG. 3 is a perspective view showing the detailed structure of the pedestal 5. As described above, the pedestal 5 is
The parts such as the seat torque load cell 2, the axial load cell 3, and the internal thread torque load cell 4 are unitized to form a main body A
(A base for fixing the measuring device, etc.), and the main body fixing screw hole 5a for the main body A is provided at several places in the circumferential direction of the contact fixing disk portion 5b. Has been drilled. Further, it is desirable that the bottom surface of the disk portion 5b has a planar shape following the shape of the contact fixing surface on the main body A side, and the surfaces that come into contact with the main body A have substantially the same shape.

The pedestal 5 is provided with a bearing arrangement hole 5c along the outer shape of the ball bearing 6. The bearing arrangement hole 5c of the ball bearing 6 is concentric with and smaller than the bearing torque load cell. A hole 5d is formed, and an axial force load cell insertion hole 5e having a smaller diameter is formed concentrically with the seat torque load cell arrangement hole 5d. Bearing arrangement hole 5c
And a stepped surface corresponding to a diameter difference between the seat surface torque load cell arrangement hole 5d and the bearing surface torque load cell arrangement hole 5d becomes a bearing groove of the seat surface torque load cell 2. In addition, the seat surface torque load cell arrangement hole 5d,
A step surface corresponding to a diameter difference from the axial load cell insertion hole 5e serves as a fixing portion of the seat torque load cell 2, and fixing screw holes 5g are provided at several places along the circumferential direction of the fixing portion. Further, an axial force load cell arranging hole 5f is formed on the bottom side of the pedestal 5 and serves as an opposing portion to which the axial load cell 3 is fixed, and is fixed at several places along the circumferential direction of the opposing portion. A screw hole 5h is provided.

The seat torque load cell 2 inserted into the inner diameter of the ball bearing 6 disposed on the pedestal 5 has a cylindrical portion 2a.
In this case, the flat plate portion 2b contacts the ball bearing 6 without interfering with the pedestal 5. The lower end 2c of the cylindrical portion 2a is
, The cylindrical portion 2a can be rotated with a slight amount from the base end. The axial load cell 3 inserted from below the insertion hole 5e of the pedestal 5 is provided in the seat torque load cell 2 arranged as described above.
Is inserted and arranged so as not to interfere with the cylindrical portion 2a.

Since the pedestal 5 is a means for fixing each part to the main body A, the pedestal 5 may be manufactured so as to be substantially integral with the main body A.
In the present embodiment, the main body A and the pedestal 5 are configured separately from each other in consideration of ease of production, ease of use, maintainability, and the like.

FIG. 4 is an enlarged perspective view showing the seat torque load cell 2, and FIG. 5 is a perspective view of the top plate 1 installed on the seat torque load cell 2. The seat torque load cell 2 includes a cylindrical portion 2a for torque detection, and a flat plate portion 2b as a bearing facing portion having a larger diameter than the cylindrical portion 2a.
The lower end portion 2c of a serves as a fixed facing portion that contacts the pedestal 5.
A through hole 2d for arranging the thin cylindrical portion 3a of the axial load cell 3 along the central axis Z is formed concentrically. Strain gauge H that detects seat torque of male screw Y
Reference numeral 1 is attached to the outer peripheral surface of the cylindrical portion 2a.

Further, at the lower end 2c as the fixed opposing portion, fixing screw holes 2e corresponding to the fixing screw holes 5g of the pedestal 5 are provided at four places along the circumferential direction around the axis Z. ing. When the fixing screw inserted into the fixing screw hole 5g of the pedestal 5 is screwed into the screw hole 2e, the seat torque load cell 2 is fixed to the pedestal 5 at its lower end 2c. A is substantially integrated with A. Further, a fixing screw hole 2f for fixing the top plate 1 is provided at four places along a circumferential direction around the axis Z in the flat plate portion 2b provided as a substantially integral structure with the upper end of the cylindrical portion 2a. Is provided.

On the other hand, the top plate 1 is a setting means for setting the male screw Y, and is provided with a setting hole 1a at the center thereof for inserting the shaft of the male screw Y as a test object. The top plate 1 is removably installed on the seat torque load cell 2. For this reason, a fixing screw hole 1 b is provided at a position corresponding to the fixing screw hole 2 f of the seat torque load cell 2. Have been.

The above-mentioned top plate 1 has one of its basic functions to set and hold the male screw Y of the test object at its measurement position. It is smaller than the external shape of Y (the diameter of the bearing surface of the screw head and the washer), and has a size in which the shaft of the male screw Y can be inserted. The top plate 1 has a male screw Y
Alternatively, a pair of rib-shaped positioning portions 1c for positioning a base material (test piece) or the like to which it is attached is provided so as to face each other across the setting hole 1a. It is better to measure with a base material such as a test piece inserted into the male screw Y than when directly setting and measuring the male screw Y (including the one with a washer) such as a bolt or the female screw X such as a nut. Sometimes, the positioning becomes easy.

The top plate 1 and the seat torque load cell 2 which are substantially integrated with each other by the screw fixing described above.
Is a first arranging means for arranging a male screw Y such as a bolt inserted into the setting hole 1a so as to be capable of screwing with the other female screw X, and a seating surface generated by the contact of the male screw Y inserted. A means for detecting torque is provided. That is, the seat torque load cell 2 having the lower end 2c fixed to the pedestal 5 is basically immovable as an integral structure with the main body A via the pedestal 5, while the periphery of the upper end side flat plate portion 2b on which the male screw Y is disposed. Is in contact with the ball bearing 6 and is rotatable, and its lower end 2c is fixed at a position closer to the center of the axis Z than the periphery of the flat plate 2b. Then, the bearing surface of the male screw Y screwed in by rotation (including the bearing surface of the male screw head and the washer surface if a washer such as a washer or a spring washer is interposed) comes into contact with the bearing surface. The applied external force acts on the flat plate portion 2b of the seat torque load cell 2 via the top plate 1 in a rotation direction about the axis Z, and the flat plate portion 2b is slightly rotated. Here, a torsion phenomenon occurs between the fixed lower end portion 2c and the torsion stress, and the torsion stress is detected by a strain gauge H1 provided on the outer peripheral surface of the cylindrical portion 3a as an appropriate place where the strain tends to concentrate.

The lower end 2c of the cylindrical portion 2a is connected to the periphery of the flat plate portion 2b to which the bearing torque of the male screw Y is applied by the axis Z.
This is in consideration of the fact that the torsion phenomenon is likely to occur due to the relationship of the moment, and the attachment of the seat torque load cell 2 to the pedestal 5. Therefore, for the purpose of detecting the seat surface torque as the distortion of the cylindrical portion 2a, the cylindrical portion 2a is not necessarily the flat plate portion 2b.
The configuration is not limited to a configuration having a smaller diameter than the periphery. For example,
Even when the cylindrical portion 2a is arranged outside the ball bearing 6 in contact with the flat plate portion 2b and away from the axis Z, substantially the same torsion effect can be obtained.

The top plate 1 can be easily attached to and detached from the seat torque load cell 2 by screw fixing. However, the reason why the top plate 1 is detachable from the seat torque load cell 2 in this manner is as follows. This is because the male screw Y having various shapes can be set. For example, if several types of top plates 1 having different diameters of the setting holes 1a through which the shaft portions of the male screws Y are inserted are prepared, it is possible to measure the male screws Y having different shaft diameters only by replacing the top plate 1. However, if the top plate 1 is provided with setting means corresponding to screws of various sizes, the top plate 1 may be integrally formed with the seat torque load cell 2 without being easily detachable, or may be formed integrally. May be performed. That is, the setting of the male screw Y and the contact with the seat surface, which are functions of the top plate 1, may be performed by the upper surface of the seat torque load cell 2.

FIG. 6 is an enlarged perspective view showing the axial load cell 3. The axial load cell 3 is a contact member serving as a distortion unit that is fastened by screwing the male screw Y and the female screw X to generate distortion in the direction of the axis Z, and has a thin cylindrical portion 3a.
A first contact portion 3b which is an upper end portion of the thin cylindrical portion 3a and which the female screw X contacts, and a second flat portion which is a lower end flat portion of the thin cylindrical portion 3a and which is in contact with and fixed to the pedestal 5. Abutment portion 3c. The thin cylindrical portion 3a has a function of concentrating axial stress applied between the first contact portion 3b and the second contact portion 3c to the thin cylindrical portion, and has a female screw in the cylindrical portion 3a. The torque load cell 4 can be inserted. The first contact portion 3b located at the upper end of the thin cylindrical portion 3a is provided with a shaft portion through hole 3d of the male screw Y, and a strain gauge H2 for detecting an axial force is provided at an appropriate position on the outer peripheral surface.
Is pasted.

The first contact portion 3b is formed by a first arranging means comprising a top plate 1 for holding a male screw Y and a seat torque load cell 2 and a second arranging means for holding a female screw X described later. The first contact portion 3b is located between
The lower surface of the second arrangement means abuts against the seating surface of the female screw X held by the second arrangement means. The second contact portion 3c is provided with four fixing screw holes 3e along the circumferential direction at positions corresponding to the fixing screw holes 5h provided in the facing portion of the pedestal 5. . The second contact portion 3c is fastened by the fixing screws inserted into the fixing screw holes 3e and 5h in a state where the second contact portion 3c is in contact with the facing portion of the pedestal 5 from below. It is fixed substantially integrally with the main body A via the pedestal 5.

The reason that the axial load cell 3 can be easily attached to and detached from the pedestal 5 by the above-mentioned screw fixing is from the viewpoint of ease of manufacture and maintenance. Therefore, it is not always necessary to have a detachable configuration for measuring the axial force, and the axial load cell 3 may be integrally formed with or integrally formed with the pedestal 5.

The axial load cell 3 has a thin cylindrical portion 3
Together with the strain gauge H2 of a, a means for detecting a tightening force generated between the male screw Y and the female screw X screwed on the axis Z as the axial force of the screw body. First, top plate 1
When the male screw Y is inserted into the upper setting hole 1a, the shaft of the male screw Y passes through the shaft through hole 3d of the first contact portion 3b. The other female screw X is held by the female screw torque load cell 4 and inserted into the thin cylindrical portion 3a from below. Thus, the male screw Y and the female screw X are opposed to each other so as to sandwich the top plate 1 and the first contact portion 3b. Is done. When the male screw Y is screwed into the female screw X, the female screw X moves in the opposite direction of the screwing of the male screw Y, that is, moves up the axis Z so as to push up the first contact portion 3b. .
Here, since the second contact portion 3c at the lower end is in contact with the pedestal 5, the thin cylindrical portion 3a formed thinner than the seat torque load cell 3 is extended substantially in the direction of the axis Z. Distortion occurs. The strain of the thin cylindrical portion 3a is detected by a strain gauge H2 attached to the outer surface thereof.

FIGS. 7A and 7B are diagrams showing the detailed configuration of the female screw torque load cell 4, wherein FIG. 7A is a front view, and FIG.
FIG. 3D is a cross-sectional view, and FIG.
The outline of the female screw torque load cell 4 constituting the second arranging means is as follows. A head 4a that locks and holds the rotation direction of the female screw X, which is an object, and a torque generated by the held female screw X causes distortion. A gage mounting shaft portion 4b formed in a shaft shape or a rod shape to be made, and a guide sleeve 10 fixed substantially integrally with the main body A while holding the gage mounting shaft portion 4b to be able to advance and retreat along the axis Z direction. It becomes. Further, a strain gauge H3 as a second detecting means is mounted near the head 4a of the gauge mounting shaft 4b. Note that the electric wire L of the strain gauge H3 has a shaft portion 4b.
It is good to be led out through the inside of the cylinder. Reference numeral 4k is a groove for passing the electric wire L.

The head 4a of the female screw torque load cell 4 is provided with a rotation preventing member 4d as holding means for holding the female screw X and preventing its rotation. In this embodiment, the rotation preventing member 4d is formed in a projection shape.
In the head 4a of this embodiment, two protrusion-shaped claws are provided as the rotation preventing member 4d so as to face each other with the axis Z interposed therebetween. In this case, a new groove is formed in the female screw X so as to be fittable with the claw of the head 4a, and the female screw X is fitted with the claw to hold the female screw X on the head 4a. The anti-rotation member 4d is not limited to a structure like the above-mentioned protrusion shape, and a fitting hole corresponding to the external shape of the female screw X is formed in the head 4a.
May be formed. For example, if the female screw X is a hexagonal nut, a hexagonal fitting hole matching the outer shape of the nut may be formed in the head 4a. In addition, the female screw X
The female screw X may be held by the head 4a across the head 4a.

The rotation preventing member 4d fixes the female screw X so that the female screw X on the top plate 1 is not rotated when the shaft portion of the male screw Y is screwed into the female screw X to be held.
The head 4a is slightly rotated by the torque applied to the female screw X. Since the mounting shaft 4b, which is integral with the head 4a, is substantially fixed to the main body A via the following guide sleeve 10, torsional stress concentrates on the relatively small gauge mounting shaft 4b to reduce distortion. Cause. This strain is detected by a strain gauge H3 for measuring internal thread torque.

Further, as the male screw Y and the female screw X are screwed together, the shaft of the male screw Y protrudes downward from the screw hole of the female screw X held on the head 4a. For this reason, there is provided a shaft escape countermeasure for allowing the shaft portion of the male screw Y to escape as described below, thereby enabling good measurement regardless of the shaft length of the male screw Y.

First, as the first countermeasure against shaft escape, the head 4a
Is provided with a shaft escape hole 4e. If there is no shaft escape hole 4e, the shaft portion that protrudes from under the female screw hole is the head 4a.
Is pressed downward, the female screw X
May fall off, so that the torque of the female screw X cannot be substantially measured. For this reason, the head 4a
A shaft escape hole 4e is formed at the center.

As a second countermeasure against shaft escape, the head 4a
The gauge mounting shaft portion 4b, which has a substantially integral structure, is movable forward and backward along the axial direction. That is, the gauge mounting shaft portion 4b inserted into the guide sleeve 10 has a notch 10a provided along the axial direction of the guide sleeve 10.
The gauge mounting shaft portion 4b is locked in the rotational direction with respect to the guide sleeve 10 and is held coaxially movably in the direction of the axis Z thereof.

As shown in FIG. 2, the guide sleeve 10 for holding the gauge mounting shaft portion 4b is substantially integral with the pedestal 5 via the intermediate block 7, the end block 11, and the like. In addition, an elastic member 4i such as a coil spring or a rubber member is detachably provided between a step 4h located substantially at the center of the gauge mounting shaft portion 4b and the end block 11, so that the gauge mounting shaft portion 4b can be mounted on the top. It is urged in the direction of the plate 1 to push the female screw X upward while maintaining the close contact between the female screw X and the head 4a.

With the above-described second shaft relief measure, the male screw Y
The protrusion of the shaft portion is large and cannot be covered only by the shaft escape hole 4e, and the front end of the shaft portion is the head 4a of the gauge mounting shaft portion 4b.
Is pressed, the gauge mounting shaft portion 4b can contract the elastic member 4i and retreat downward, so that the male screw Y
Is not hindered. However, in order to prevent the female screw X from dropping off from the head 4a at the time of retreat, it is necessary that the fitting between the female screw X and the rotation preventing member 4d can be maintained even when the gauge mounting shaft portion 4b retreats downward. . For example, it is preferable to make the shape of the projection of the head 4a higher than the distance in which the gauge mounting shaft 4b can move forward or backward, or to form the fitting groove deeper.

Next, the attachment / detachment mechanism of the second arranging means including the female screw torque load cell 4 will be described. The female screw torque load cell 4 has a substantially integral structure with the pedestal 5 at the time of measurement, but can be easily attached and detached so that the female screw X can be easily set on the head 4a. Here, the integrated structure in which the top plate 1, the bearing surface torque load cell 2, the ball bearing 6, and the axial force load cell 3 are held on the pedestal 5 is referred to as an "upper unit". The female screw torque load cell 4, the intermediate block 7, and the end An integrated structure constituted by the block 11, the grip cover 9, and the like is referred to as a “lower unit”, and the configuration of the lower unit will be mainly described.

The female screw torque load cell 4 of this embodiment is
Guide sleeve 1 press-fitted and fixed to intermediate block 7
Inserted in 0. The inner peripheral surface of the guide sleeve 10 and the large-diameter portion 4c of the gauge mounting shaft portion 4b can be connected by a keyway, spline, serration, or the like.

The intermediate block 7 holding the female screw torque load cell 4 is screw-fixed to the end block 11, and a grip cover 9 into which the cam member 8 is press-fitted is mounted outside the intermediate block 7. The lower unit assembled in this manner is fixed to the main body A substantially via the axial load cell 3 and the pedestal 5 while disposing the female screw X at the measurement position by the following attachment / detachment mechanism.

As shown in FIG. 2, the attachment / detachment mechanism for the lower unit includes a fitting structure between the intermediate block 7 and the upper unit, and a cam mechanism for performing this fitting operation. As a fitting structure for fixing the intermediate block 7 holding the female screw torque load cell 4 to the upper unit, claw members 7a are attached to the outer peripheral portion of the intermediate block 7 at three equal positions along the circumferential direction. I have. Each claw member 7a has a key-shaped claw 7b at its upper part, a rotation shaft part 7c near its center, and a contact area part 7d at its lower part, and the claw part 7b based on the rotation shaft part 7c. Contact area 7d
Are rotatably arranged. An urging member 7e using a spring ring such as an O-ring abuts against the contact area 7d on the outside, and the cam portion 8a of the cam member 8 comes into contact with the urging member 7e from the inside. The convex portion 7f provided at the tip of the intermediate block 7 is fitted with the concave portion 3g of the axial force load cell 3 provided corresponding to the convex portion 7f, and controls the rotation of the male screw torque load cell 4 due to the generation of the screw portion torque. Lock.

One of the upper units has the claw member 7a.
In this embodiment, an engaging structure is provided on the lower surface of the second contact portion 3c of the axial load cell 3 as such engaging means. 3f is formed. Of course, such an engagement structure 3
This is not limited to the case where f is directly formed and provided, and the same functional member is attached to the axial load cell 3 as a separate member,
Alternatively, the lower part of the pedestal 5 may be processed so as to be integrally formed with the pedestal 5.

The grip cover 9 of the lower unit has a substantially cylindrical shape having a grip function when the lower unit is detached from the pedestal 5, and the cam member 8 is press-fitted inside. Then, the cam member 8 and the grip cover 9
The end block 11 is brought into contact with the end portions to form a substantially integral structure with the end block 11. The end block 11 and the grip cover 9 are relatively rotatable. In this embodiment, the cam member 8 is press-fitted and fixed to the grip cover 9.
May be provided integrally with the inside of the grip cover 9.

FIG. 8 is a perspective view showing the shape of the cam member 8. The rotation of the cam member 8 causes the intermediate block 7 to rotate.
Is rotated. For this reason, the cam member 8 is formed with three cam portions 8a which are notched obliquely in one circumferential direction at positions corresponding to the three claw members 7a of the intermediate block 7. As shown in the cross-sectional view of FIG. 2, in the state of engagement with the engagement structure 3f of the axial load cell 3, the contact area 7d of the claw member 7a is accommodated in the cam portion 8a at each position. Here, when the operator turns the end block 11 while holding the grip cover 9, the cam portion 8a moves in the circumferential direction with respect to the contact region 7d, so that the contact region 7d is pushed outward.
When the cam portion 8a pushes the contact region 7d, the claw member 7a rotates with the rotation shaft portion 7c as a reference, and the claw portion 7b is returned inward in the center direction. As a result, the engagement between the claw portion 7b and the engagement structure 3f is released, and the lower unit together with the grip cover 9 can be easily removed from the upper unit. The rotation direction when the engagement is released is a direction in which the male screw Y and the female screw X, which are the test objects, are not loosened when viewed as a relative rotation direction with respect to the cam portion 8a of the end block 11. That is, it is desirable to set the direction opposite to the co-rotating direction of the female screw X received by the engagement of the male screw Y.

As described above, in addition to the female screw torque load cell 4 having the function of holding and detecting the torque of the female screw X, the lower unit has an intermediate block 7 and an end block 11 for fixing it to the main body A side. Although the original function and role of the lower unit are to function for arranging and fixing the female screw X and for detecting the distortion generated by the minute rotation of the female screw X, the lower unit has an essential function and role. is there. Therefore, if it has at least the head portion 4a for fixing the female screw X for torque detection, the gauge mounting shaft portion 4b for taking out the female screw torque as strain, and the strain detecting means, the end block 11, the cam member 8 However, the present invention is not limited to the configuration having the grip cover 9 and the like.

Next, the operation of this embodiment will be described. First, the upper unit in which the top plate 1, the bearing surface torque load cell 2, the ball bearing 6, and the axial load cell 3 are mounted on the pedestal 5 is fixed to the main body A by bolts inserted into the main body fixing screw holes 5a. Is done. On the other hand, the torque load cell 4 is inserted into the guide sleeve 10 in the intermediate block 7, and in this state, the guide sleeve 10 is pressed into the intermediate block 7 and fixed.
And an elastic member 4i for urging the internal thread torque load cell 4
(Compression spring, rubber, etc.) and the grip cover 9 into which the cam member 8 is press-fitted are fixed on the end block 11 to form a lower unit. On the head 4a of the female screw torque load cell 4 of the lower unit, a female screw X (a nut or the like) of the test object is fixed by its rotation preventing member 4d. At this time, it is necessary to provide in advance a groove on the surface of the female screw X in which the projection serving as the rotation preventing member 4d can be fitted.

The lower unit in which the female screw X is set is rotated by rotating the grip cover 9 while holding the end block 11 so as to mount the lower unit on the upper unit installed in the main body A (holding the grip cover 9). (The end block 11 may be rotated in reverse.) The relative rotation of the cam member 8 with respect to the claw member 7a causes the claw portion 7b to retract toward the center axis Z against the urging force of the urging member 7e. Keep it. In this state, the operator moves the end block 11
, The female screw torque load cell 4 of the lower unit is inserted into the axial load cell 3 of the upper unit, and the grip cover 9 is rotated in the direction opposite to the direction in which the urging of the claw member 7a was released earlier (the rotation direction is the lower direction). The claw portion 7b is engaged with the engagement structure 3f of the axial force load cell 3 by the urging member 7e by moving the unit upward (to the right in the clockwise direction when looking up the upper unit from the unit). In this way, the lower unit is held by the upper unit, is fixed substantially integrally to the same main body A, and the female screw X is arranged at the measurement position. In addition, each of the strain gauges H1, H2, and H3 is connected to the conversion unit B.
And the data measured by the converter B is displayed on the display C.

The male screw Y of the test object is passed through a washer such as a washer, and the shaft is inserted into a setting hole 1a provided at the center of the top plate 1 of the upper unit. This completes the preparation for simultaneously measuring and determining the bearing torque of the male screw Y, the torque of the female screw X, and the axial force of the screw body when the male screw Y and the female screw X are fastened.

The seat torque of the male screw Y at the time of screwing is determined by the torsional moment acting on the male screw Y fixed via the top plate 1 at the lower end of the seat torque load cell 2 fixed substantially integrally with the main body A side. Is detected as distortion generated in the cylindrical portion 2a. This distortion is measured as a voltage change by a strain gauge H1 attached to the outer peripheral surface of the cylindrical portion 2a, and the voltage measured here is determined by the conversion unit B based on the previously measured comparison data (conversion data). N
M) is automatically converted to m) and displayed on the display C as the seat torque of the male screw Y.

With the insertion of the male screw Y, the female screw X fixed to the head 4a of the female screw torque load cell 4 tries to rotate in the screwing rotation direction of the male screw Y. 7 and is fixed substantially integrally with the main body A side. For this reason, the gauge mounting shaft 4
The strain generated in b is measured as a voltage by a strain gauge H3 attached to the shaft portion 4b. The voltage measured here is based on the comparison data measured in advance, and the conversion unit B
Is automatically converted to a torque and displayed on the display C as a female screw torque.

When the fastening of the male screw Y and the female screw X is further advanced, the female screw X fixed to the head 4a of the female screw torque load cell 4 tends to move in the male screw direction (upward of the axis Z), and The contacting first contact portion 3b is pushed upward, and the second contact portion 3c at the lower end thereof is fixed substantially integrally to the main body A side. At this time, the thin cylindrical portion 3a of the axial load cell 3 which is thinner than the cylindrical portion 2a of the first arranging means is extended in the direction of the axis Z by a small amount. This strain is measured as a voltage by the strain gauge H2, and the conversion unit B automatically converts the measured voltage in the axial force direction based on the comparison data measured in advance, and this is the screwing of the male screw Y and the female screw X. It is displayed on the display C as an axial force.

In the first embodiment described above, the axial force acting in the axial force direction between the male screw Y and the female screw X is measured as the amount of extension of the cylindrical portion 3a of the axial load cell 3. Not limited to such measurement, distortion in the compression direction of the cylindrical portion 3a may be detected and measured. Hereinafter, a second embodiment in which the axial force of the screw body can be measured as the compression amount of the thin cylindrical portion 3a will be described.

FIGS. 9 and 10 are sectional views showing the structure of the axial force measuring device according to the second embodiment. The outline of the configuration of the device of the second embodiment is substantially the same as that described in the first embodiment, and the top plate 1 for holding the male screw Y is provided.
, A seat torque load cell 2 that generates distortion by coming into contact with the seat surface of the male screw Y, and an axial load cell 3 that is axially fastened and compressed between the male screw Y and the female screw X
A female screw torque load cell 4 that holds a female screw X screwed to the male screw Y and generates distortion due to this torque;
A strain gauge H1 attached to the seat torque load cell 2 to detect the strain, a strain gauge H3 attached to the female screw torque load cell 4 to detect the strain, and a strain gauge H2 attached to the axial load cell 3 to detect the strain. And a pedestal 5 on which the above members are mounted as a substantially integrated unit, and a main body A for fixing the pedestal 5.

The axial load cell 3 of the first embodiment is fixed to the pedestal 5 by a second contact portion 3c (fixed flat portion) at the other end, whereas the second embodiment shown in FIGS. In the axial load cell 3 of the second embodiment, the second contact portion 3c is located between the male screw Y and the female screw X apart from the pedestal 5. That is, the first contact portion 3b is the same as that of the first embodiment in contact with the female screw X. However, in the axial load cell 3 of the second embodiment, the second contact portion 3c is connected to the male screw Y.
And a female screw X and fixed to the male screw Y side. The second contact portion 3c, which is the upper end of the axial load cell 3, is fixed to the top plate 1 or the seat torque load cell 2, and also in this case, the strain gauge H2 is a thin cylinder located between the male screw Y and the female screw X. It is attached to the part 3a. In this way, the thin cylindrical portion 3a is
And a configuration arranged between each seat surface with the female screw X, it is easy to measure the male screw Y having a relatively long axial length.

As shown in FIG. 10, the second contact portion 3c of the axial load cell 3 is fixed by sandwiching the peripheral edge between the top plate 1 and the seat torque load cell 2. It can also be.

In the axial force measurement of the second embodiment, the male screw Y
When the thin cylindrical portion 3a is fastened between the female screw X and the top plate 1 on which is disposed, the strain is measured in the shrinking direction by the strain gauge H2 attached to the outer surface thereof. By converting this amount of distortion into an axial force, a fastening force between the male screw Y and the female screw X when actually screwed together can be obtained.

In each of the embodiments described above, a case is described in which a male screw Y (bolt or the like) is disposed on the top plate 1 and a female screw X (nut or the like) is disposed from below and screwed thereto. are doing. However, conversely, even if the female screw X is disposed on the top plate 1 and the male screw Y is held and screwed into the female screw torque load cell 4, the torque and the axial force must be measured in the same manner as in the above embodiment. Can be. In this arrangement, the seat torque of the female screw X is measured by the strain gauge H1 attached to the seat torque load cell 2, and the male screw Y torque is measured by the strain gauge H3 attached to the female screw load cell 4. When the arrangement of the screws is reversed in this way, the strain gauges H1 and H3 for measuring the torque are renewed in order to make the respective comparison data for converting the measured voltage into the torque correspond to such an arrangement. Will be created.

(Fully Automatic Type) FIG. 11 is a view showing a case where the measuring apparatus of FIG. 2 is a fully automatic type measuring apparatus.
The same parts as those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 11, a rotation fitting portion 100 having a fitting hole substantially the same as the head portion of the male screw Y is fitted into the head of the male screw Y, and a rotation transmitting member such as a shaft or gear is driven by a motor 102. The male screw Y is rotated through 101. The rotation of the motor 102 starts when a switch (not shown) of the main body is turned on. The screw starts screwing by this rotation, and each strain gauge H1, H2, H3 and the conversion part B measure the axial force and each seat torque.

When the control section 103 detects that each of the predetermined measured values, the maximum measured value, or the reference value (a value based on the screwing limit) is reached, the rotation of the motor 102 is stopped. Alternatively, after reaching the measured value, the maximum value, or the reference value, the control unit 104 may instruct the motor 102 to rotate in the reverse direction. In this case, the stop is detected by detecting the rotation torque of the motor 102 to detect the idling state, or by measuring the axial force and the seating torque in the reverse rotation state, so that the measurement result becomes substantially “0”. Feedback control may be performed. Note that the motor 102 can also be stopped by turning off a switch on the main body.

FIG. 12 is a block diagram showing an example of an electrical unit for this measurement, and FIG. 13 is a block diagram showing an example of a control unit. Electrical part 125
Is an amplifier 125a, an A / D converter 125b, a control unit 126, a display unit 125c, and a switch unit 12.
1 is provided.

As shown in FIG. 13, the control means 126 includes a storage means 126a, a comparing means 126b, a counting means 126c, a reverse rotation time determining means 126d, a control signal generating means 126e, and a mode switching means 126f. And can be configured using a microcomputer. The storage unit 126a can store one or both of a set value and a measured value.

The comparing means 126b is connected to the measuring means 106
The measured value measured by c and the set value stored in the storage unit 126a can be compared. Further, the comparing unit 126b compares the measured value stored in the storage unit 126a with the measured value measured by the measuring unit 106c thereafter.

The counting means 126c is provided with the switch 1
The rotation time based on the number of rotations from when the motor 21 is turned on to when the motor 102 stops can be counted. The reverse rotation time determining means 126d calculates the motor 10 based on the rotation time based on the number of rotations counted by the counting means 126c.
2 can be determined.

The control signal generating means 126e can send a measurement start signal to the strain gauge 106c and send a rotation drive signal to the motor 102. The mode switching unit 126f includes a break value measurement mode (steps S5 to S7 described later), an intensity value measurement mode (steps S8 to S11 described later), and a peak value measurement mode (steps S12 to S17 described later). Mode).

FIG. 14 is a flowchart showing an example of the control program. When the program is executed, in step S1, the motor 102 is started to rotate at a low speed until the predetermined time in step S2 elapses, and after the predetermined time elapses, the process proceeds to step S3. In step S3, the counting means 126c is operated, and the process proceeds to step S4. In step S4, the rotation speed of the motor 102 is increased and the motor 102 is rotated at high speed, and the process proceeds to step S5.

In step S5, the axial force and the bearing torque are measured based on the electric signal output from the strain gauge 106c, and the flow advances to step S6. In step S6, it is determined whether or not the electric signal output from the strain gauge 106c has suddenly fluctuated. If the electric signal is broken, the process proceeds to step S7. If not, the process proceeds to step S8. In step S7, the measured value is displayed on the display unit 125c as a break value, and the process proceeds to step S18. Step S
At 8, the axial force and the seat torque are measured based on the electric signal output from the strain gauge 106c, and the process proceeds to step S9. In step S9, the measured value is stored in the storage means, and the process proceeds to step S10.

In step S10, the measured value stored in step S9 is compared with the set value. If the measured value is larger, the process proceeds to step S11, and if not, the process proceeds to step S12. In step S11, the measured value is displayed on the display unit 125c as an intensity value.
Proceed to 18. In step S12, the axial force and the seat torque are measured based on the electric signal output from the strain gauge 106c, and the process proceeds to step S13. In step S13, the measured value measured in step S12 is stored in the storage unit,
Proceed to step S14. In step S14, the axial force and the seat torque are measured based on the electric signal output from the strain gauge 106c, and the process proceeds to step S15.

In step S15, the stored value (measured value) stored in step S13 is compared with the measured value measured in step S14. If the measured value is larger, the process proceeds to step S16. To step S17
Proceed to. In step S16, the measured value of step S12 stored in the storage unit is updated to the measured value of step S14 and stored, and the process returns to step S14 to measure the tensile force again.

In step S17, the stored value is displayed on the display means 125c as a peak value, and the flow advances to step S18. In step S18, the motor 102 is temporarily stopped,
Proceed to step S19. In step S19, the counting means 26c operated in step S3 is stopped, and the process proceeds to step S20.

In step S20, the counting means 26c
Motor 2 for a time corresponding to the number of revolutions counted by
0 is reversed, and the process proceeds to step S21. Step S21
Then, the motor 102 is stopped.

(Screw Evaluation System) FIG. 15 is a block diagram showing an example of the screw evaluation system. FIG.
As shown in FIG. 5, the screw evaluation system is a measuring jig shown in FIG. 2 and FIG.
201, a converter 202 for converting a voltage change of the strain gauge into a torque, a controller 203 for performing a design evaluation based on the conversion processing result by the converter 202, a display unit 204 for displaying the design evaluation result, and a design evaluation. And a transmission unit 205 for transmitting the result to the designer via a network such as an intranet or the Internet.

According to this evaluation system, it is possible to determine whether or not to use the “screw” measured by the above-described measuring device, to use the screw as it is if the measurement result passes, or to prompt a design change if the measurement result fails. In the case of a pass / fail, the network and the control unit of the device can be linked to transmit the registered design document to the designer who created it. In addition, by making the control unit determine whether or not the recommended “screw” is used, it is possible to recommend a “screw” suitable for designing the screw. The present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the gist of the present invention.

[0097]

As described above, the axial force measuring device for a threaded body according to the present invention comprises a male screw or a female screw at one end and two or more arranging means fixed to substantially the same body at the other end. A device for measuring a fastening force when a male screw and a female screw disposed opposite to each other are screwed with each other, wherein a contact portion for contacting a bearing surface of one screw and a fixing portion for fixing to a main body side. A first arranging means having a first arranging means, a second arranging means which locks and holds the rotation direction of the other screw screwed with the screw of the first arranging means, Since it has axial force detecting means for converting distortion caused by fastening of the male screw or female screw into an electric signal, and conversion processing means for converting the electric signal generated by the axial force detecting means as an axial force, it is integrated. By a single measuring device It can be measured with the external thread of bets like, a fastening force in the axial direction in a state where the internal thread of the nut or the like is actually screwed.

Further, the jig for measuring the axial force of the screw body of the present invention is as follows.
A jig for measuring a fastening force when a male screw and a female screw arranged opposite to each other are relatively screwed by two or more arranging means which hold a male screw or a female screw at one end and are fixed to substantially the same main body at the other end. Wherein a first arranging means having a contact portion for contacting the bearing surface of one of the screws and a fixing portion for fixing to the main body side, and screwed with the screw of the first arranging means Since it has second arrangement means for locking and holding the rotation direction of the other screw, and axial force detection means for converting distortion into an electric signal by fastening the oppositely disposed male screw or female screw, A single measuring device integrated into a unit can measure the fastening force in the axial direction in a state where a male screw such as a bolt and a female screw such as a nut are actually screwed.

The method for measuring the axial force of a screwed body according to the present invention is as follows.
In the axial force measurement method of the screw body for measuring the fastening force when the male screw and the female screw are relatively screwed together, one of the pair of screws is rotatably arranged with respect to the main body to the first arrangement means. The other is fixedly arranged with respect to the main body to the second arrangement means, and by the screwing of the pair of screws, a compressive force or a tensile force is applied to the axial force detecting means to reduce the distortion of the axial force detecting means. Since the conversion process is performed into the axial force by the pair of screws, the fastening force in the axial direction when the male screw such as a bolt and the female screw such as a nut are actually screwed together can be measured.

Further, the evaluation system for a screw body according to the present invention comprises:
In a screw body evaluation system that measures and evaluates the fastening force when the male screw and the female screw are relatively screwed together, first arrangement means for rotatably disposing one of the pair of screws,
A second disposing means for fixing and disposing the other, an axial force detecting means interposed between the pair of screws, and applying a compressive force or a tensile force by screwing the pair of screws together; and the axial force detecting means A conversion processing means for converting the distortion of the means into an axial force by the pair of screws, and a design evaluation means for performing a design evaluation of the screw based on the conversion processing result; and Since the use is determined, it is determined whether or not to use the measured "screw", and if the measurement results pass, it can be used as is, and if it does not pass, the design change can be prompted, and if it passes or fails, the net and this By linking the control unit of the apparatus, the design document registered in advance can be transmitted to the designer who created the design document. In addition, by making the control unit determine whether or not the recommended “screw” is used, it is possible to recommend a “screw” suitable for designing the screw.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a measuring device according to a first embodiment.

FIG. 2 is a cross-sectional view showing the entire configuration of the measuring device of the first embodiment.

FIG. 3 is a perspective view showing a detailed configuration of a pedestal according to the first embodiment.

FIG. 4 is an enlarged perspective view showing a seat torque load cell according to the first embodiment.

FIG. 5 is a perspective view of a top plate installed on a seat torque load cell.

FIG. 6 is an enlarged perspective view of the axial load cell according to the first embodiment.

7A and 7B show a detailed configuration of a female screw torque load cell according to the first embodiment, wherein FIG. 7A is a front view, FIG. 7B is a sectional view taken along line DD, and FIG. 7C is a view showing a guide sleeve.

FIG. 8 is a perspective view showing a shape of a cam member used for an attachment / detachment mechanism of a female screw torque load cell.

FIG. 9 is a cross-sectional view illustrating an entire configuration of an axial force measuring device according to a second embodiment.

FIG. 10 is a sectional view showing a configuration in which an axial load cell according to the second embodiment is also fixed to a seat torque load cell.

11 is a diagram showing a case where the measuring device of FIG. 2 is a fully automatic type measuring device.

FIG. 12 is a block diagram showing an example of an electrical unit for measurement by the apparatus of FIG.

FIG. 13 is a block diagram illustrating an example of a control unit in FIG.

FIG. 14 is a flowchart showing an example of a control program.

FIG. 15 is a block diagram illustrating an example of a screw evaluation system.

[Explanation of symbols]

 A Body H1 Strain gauge (first detecting means) H2 Strain gauge (axial force detecting means) H3 Strain gauge (second detecting means) X Female thread Y Male thread Z Axis of screwed body 1 Top plate (First arranging means) 2 Seating surface torque load cell (first arrangement means) 2a Cylindrical part of first arrangement means 2b Flat plate part (bearing opposed part) 2c Lower end part (fixed opposed part) 3 Axial force load cell (axial force detection means) 3a Contact Thin cylindrical portion of member 3b First contact portion 3c Second contact portion 3f Engagement structure 3g Recess 4 Female screw torque load cell (second arrangement means) 4a Head 4b Gauge mounting shaft 4d Rotation prevention member (holding) Means) 4e Shaft escape hole 4g Pin 6 Ball bearing (bearing) 7f Convex part 10 Guide sleeve 10a Notch part 100 Rotary fitting part 101 Rotation transmitting member 102 Motor 103 Control part 201 Osamu 202 conversion unit 203 control unit (design evaluation means) 204 Display unit 205 transmission unit

Claims (31)

[Claims] 1. An axial force when relatively opposed male and female screws are screwed together by two or more arranging means which hold a male or female screw at one end and are fixed to substantially the same main body at the other end. A first arrangement means having a contact portion for contacting the bearing surface of one of the screws and a fixing portion for fixing the screw to the main body side; and a screw of the first arrangement means. Second arrangement means for locking and holding the rotation direction of the other screw that is screwed together, and axial force detection means for converting distortion generated by fastening of the externally arranged male screw or female screw to an electric signal. And a conversion processing means for converting the electric signal generated by the axial force detection means as an axial force. 2. The axial force detecting means has a first end disposed between the first arranging means and the second arranging means, the first abutment being in contact with a seat surface of either a male screw or a female screw. Part, a cylindrical member formed in a thin cylindrical shape having a second contact portion fixed at the other end and substantially integrally with the main body side,
The axial force measuring device for a screw body according to claim 1, further comprising a strain gauge attached to a cylindrical portion of the cylindrical member and detecting a strain at the cylindrical portion. 3. The second contact portion is not fixed to the main body, but is disposed between the first disposing means and the second disposing means. The second contact portion is fastened by the screw body and shrunk to a cylindrical portion. The axial force measuring device for a screw body according to claim 1, wherein a directional distortion is caused. 4. A bearing opposing portion which contacts the main body side via a bearing on a side of the first arranging means which comes into contact with the bearing surface of the screw, and wherein the contact portion is provided with respect to the main body. The axial force measuring device for a screw body according to any one of claims 1 to 3, wherein the axial force measuring device is capable of being twisted. 5. An axial other end side of the first arrangement means,
5. A fixed facing portion fixed to the main body at a position closer to the axis of the screw body than the bearing facing portion.
An apparatus for measuring the axial force of a screw body according to claim 1. 6. The first disposing means has a cylindrical portion along the axis of the screw body, and one end of the cylindrical portion is fixed substantially integrally with the bearing opposing portion, and the cylindrical portion has The axial force measuring device for a screw body according to any one of claims 1 to 5, wherein the other end is fixed substantially integrally with the main body side. 7. A shaft of a screw body, wherein a thin cylindrical portion of said axial force detecting means is provided in a cylindrical portion of said first arranging means, and said second arranging means is further provided in a thin cylindrical portion of said axial force detecting means. The axial force measuring device for a screw body according to claim 1, wherein the axial force measuring device is provided concentrically on a line. 8. The screwed body according to claim 1, wherein the other end in the axial direction of the second arranging means is fixed substantially integrally with the main body in the direction of rotation. Axial force measuring device. 9. The apparatus according to claim 1, wherein said second arranging means is movably installed along an axis of the screw body.
9. The axial force measuring device for a screw body according to any one of claims 8 to 8. 10. The screw body according to claim 1, further comprising a holding means for engaging the screw to be arranged, on a side of the second arrangement means for locking the screw. Axial force measuring device. 11. The holding means is provided with a projection at one end of the second arranging means, and the projection can be engaged with a notch formed in advance on the screw. The axial force measuring device for a screw body according to claim 10, wherein: 12. The axial force measuring device for a screwed body according to claim 10, wherein said holding means has a fitting structure substantially the same as the outer diameter shape of said screw. 13. The second arrangement means according to claim 1, wherein a shaft escape hole is provided so that a shaft portion of a male screw screwed into the held female screw does not interfere. An apparatus for measuring the axial force of a screw body according to claim 1. 14. A mechanism according to claim 1, further comprising a detachable mechanism provided between the main body on which the first arranging means is installed and the second arranging means. An apparatus for measuring the axial force of a screw body according to claim 1. 15. A method for measuring an axial force of a screwed body for measuring a fastening force when a male screw and a female screw are relatively screwed together, wherein one of the pair of screws is rotated relative to the main body by a first arranging means. And the other is fixed to the main body with respect to the second arranging means, and a compressive force or a tensile force is applied to the axial force detecting means by screwing the pair of screws together. A method for measuring the axial force of a screw body, wherein the distortion of the means is converted into the axial force of the pair of screws. 16. The axial force detecting means has one end of a cylindrical member formed in a thin cylindrical shape abutting on a bearing surface of either a male screw or a female screw, and the other end fixed substantially integrally with the main body side. The method for measuring the axial force of a screw body according to claim 15, wherein the strain at the cylindrical portion is detected by a strain gauge attached to the cylindrical portion of the cylindrical member. 17. The method for measuring the axial force of a screwed body according to claim 16, wherein said axial force detecting means is tightened by said screwed body to generate distortion in a contraction direction. 18. The apparatus according to claim 15, wherein said first arrangement means is distorted by a torsional moment.
18. The method for measuring the axial force of a screwed body according to any one of claims 17 to 17. 19. The other end in the axial direction of the second arrangement means,
The method for measuring the axial force of a screwed body according to any one of claims 15 to 18, wherein the screw is fixed substantially integrally with the main body in the rotation direction. 20. The apparatus according to claim 1, wherein said second arranging means is movably installed along an axis of the screw body.
20. The method for measuring an axial force of a screwed body according to any one of 5 to 19. 21. The screw arranged on the side of the second arrangement means for locking the screw engages with the side of the second arrangement means for locking the screw. 20. The method for measuring an axial force of a screwed body according to any one of 20. 22. The screw according to claim 15, wherein said second arranging means escapes the shaft portion so that the shaft portion of the male screw screwed into the held female screw does not interfere. A method for measuring the axial force of coalescence. 23. The screw body according to claim 15, wherein a portion between the main body on which the first arranging means is installed and the second arranging means is detachable. Axial force measurement method. 24. Axial force when relatively opposed male and female screws are screwed relative to each other by two or more arranging means which hold a male or female screw at one end and are fixed to substantially the same main body at the other end. A jig for measuring the first arrangement means having a contact portion for contacting the bearing surface of one of the screws and a fixing portion for fixing to the main body side; Second arrangement means for locking and retaining the rotation direction of the other screw screwed with the screw, and axial force detection means for converting distortion into an electric signal by fastening the male screw or female screw arranged opposite to each other. A jig for measuring an axial force of a screw body, comprising: 25. A first abutment, wherein one end of the axial force detecting means is arranged between the first arranging means and the second arranging means and is in contact with a seat surface of either a male screw or a female screw. Department and
It is constituted by a cylindrical member formed in a thin cylindrical shape having a second contact portion fixed to the main body side and the main body side at the other end, and this cylindrical portion is engaged with an external thread and an internal thread. 25. The jig for measuring an axial force of a screw body according to claim 24, wherein the jig is distorted by the jig. 26. The jig for measuring an axial force of a screwed body according to claim 25, wherein said axial force detecting means has a strain gauge for detecting distortion of a cylindrical portion of said cylindrical member. 27. A jig for measuring an axial force of a screwed body according to claim 24, wherein said second arranging means is detachable from the main body. 28. A jig for measuring an axial force of a screwed body according to claim 24, wherein said second arranging means has means movable along an axis of the screwed body. 29. The apparatus according to claim 24, wherein the second arranging means has a projection shape for fitting into a recess provided in the screw in advance, thereby locking the rotation direction of the screw. Jig for measuring axial force of screw body. 30. The threaded body according to claim 24, wherein said second arranging means locks the rotation direction of the screw by providing a fitting structure substantially the same as the outer diameter of the screw. Axial force measurement jig. 31. A threaded member evaluation system for measuring and evaluating a fastening force when a male screw and a female screw are relatively screwed into each other, wherein the first disposing means rotatably disposes one of the pair of screws. Second arrangement means for fixedly disposing the other; axial force detection means interposed between the pair of screws and applying a compressive force or a tensile force by screwing the pair of screws together; A conversion processing means for converting the distortion of the force detection means into an axial force by the pair of screws; and a design evaluation means for performing a design evaluation of the screw based on the conversion processing result, based on the design evaluation result. An evaluation system for a screw body, wherein a use of a screw is determined.