KR102181780B1 - Contact type measurement device for axial force - Google Patents

Abstract

Provided is a contact type axial force measurement device capable of predicting the axial force of a bolt by a linear correlation obtained before applying fastening force to the bolt. The contact type axial force measurement device comprises: a deformable body through which a bolt penetrates in the longitudinal direction; a first deformable blade provided in one side of the deformable body and fixed to one side of the bolt; a second deformable blade provided in the other side of the deformable body and fixed to the other side of the bolt; a deformation detection sensor provided in one surface of the deformable body and detecting deformation rates of one side of the bolt and the other side of the bolt; and an axial force determination part that determines axial force applied to the bolt by fastening force applied to the bolt based on the deformation rates detected by the deformation detection sensor.

Description

Contact type measurement device for axial force

The present invention relates to a contact-type axial force measuring device, and in detail, based on a linear correlation between the deformation rate of the deformation detection sensor obtained before applying the tightening force to the bolt and the amount of deformation in the longitudinal direction of the bolt, contact It is related to the type axial force measuring device.

In the field of construction and machinery, in tightening bolts and nuts to fix a fixed object, measuring physical quantities is an important factor in terms of safety and economic efficiency.

Among them, in order to measure the axial force of a bolt that penetrates a fixed object but is fastened with a nut, conventionally, a sensor is directly attached to the bolt, and the physical quantity of the bolt that changes according to the fastening of the bolt and the nut is measured as the sensor. A measuring device for measuring axial force is used.

For example, Korean Patent Laid-Open Publication No. 1998-0003507 discloses a bolt forming a through hole perpendicular to the bolt axial direction in the bolt shank, and forming a connection groove in the bolt axial direction so that it can be connected to the through hole from the bolt head. Preparing step, attaching two strain gauges in a 180° phase to the bolt shank part, and drawing the wire of the strain gauge to the outside through the through hole and the connection groove to connect the strain gauge measuring equipment to the strain gauge installation step, and the A method for measuring bolt axial force is disclosed, including the step of measuring the bolt axial force with the strain gauge measuring device by fastening the prepared bolt as described above.

However, the method of directly attaching the strain gauge to the bolt is not only unsuitable for use in mass production sites, but also increases the unit cost by using a specially manufactured bolt to attach the strain gauge and is inefficient in terms of economy.

Therefore, there is a need for a countermeasure to solve the above-described problem.

One technical problem to be solved by the present invention is to provide a contact-type axial force measuring device capable of predicting the axial force of the bolt by a linear correlation obtained before applying a fastening force to the bolt.

Another technical problem to be solved by the present invention is to provide a contact-type axial force measuring device that can predict the axial force of a bolt in real time.

The technical problem to be solved by the present invention is not limited to the above.

In order to solve the above-described technical problem, a contact-type axial force measuring device is provided.

The contact-type axial force measuring device may include a deformable body through which a bolt passes in a longitudinal direction, a first deformable blade provided on one side of the deformable body and fixed to one side of the bolt, and the other side of the deformable body. A second deformation blade provided and fixed to the other side of the bolt, a deformation detection sensor provided on one side of the deformation body, and detecting a deformation rate of one side of the bolt and the other side of the bolt, and the bolt It may include an axial force determination unit that determines an axial force applied to the bolt based on a strain detected by the strain detection sensor by the applied fastening force.

According to an embodiment, the axial force determination unit may determine the axial force applied to the bolt in consideration of a linear correlation between the strain and the amount of deformation in the longitudinal direction of the bolt due to a fastening force applied to the bolt.

According to an embodiment, the linear correlation may depend on the shape and material of the first and second deformable wings and the deformable body.

According to an embodiment, the deformable body may be fixed to the bolt body exposed to the outside from the bolt by the first and second deformable wings.

According to an embodiment, the bolt may fasten the first fixing object and the second fixing object through a corresponding nut.

According to an embodiment, the deformable body may be fixed between the first and second fixing objects.

According to an embodiment, the deformable body may be fixed in the longitudinal direction of the bolt by the first and second deformable blades.

According to an embodiment, the deformation according to the fastening force applied to the bolt may deform the deformation detection sensor through the first and second deformable blades, through the deformable body.

According to an embodiment, the thickness of the first and second deformable blades may be thinner than the pitch of the bolt.

According to an embodiment, the deformable body may further include an opening/closing part so that the bolt can be accommodated into the deformable body.

According to an embodiment of the present invention, a deformable body in which a bolt passes in the longitudinal direction, a first deformable wing provided on one side of the deformable body and fixed to one side of the bolt, and the other side of the deformable body A second deformation blade provided and fixed to the other side of the bolt, a deformation detection sensor provided on one side of the deformation body, and detecting a deformation rate of one side of the bolt and the other side of the bolt, and the bolt A contact-type axial force measuring device including an axial force determination unit for determining an axial force applied to the bolt based on a strain detected by the deformation detection sensor by an applied fastening force may be provided.

Accordingly, a linear correlation between the strain sensed by the strain detection sensor and the amount of deformation in the longitudinal direction of the bolt due to a fastening force applied to the bolt may be obtained before applying the fastening force.

Therefore, when a fastening force is applied to the bolt, the axial force of the bolt can be easily and quickly predicted by simply measuring the deformation of the deformable body through the axial force measuring unit.

In addition, since the contact-type axial force measuring device according to an embodiment can be used in a detachable manner, convenience of use can be improved.

1 to 3 are views for explaining a contact-type axial force measuring apparatus according to an embodiment of the present invention.
4 and 5 are views for explaining an axial force measuring unit according to an embodiment of the present invention.
6 to 8 are views for explaining an axial force determination unit according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical idea of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art.

In the present specification, when a component is referred to as being on another component, it means that it may be formed directly on the other component or that a third component may be placed between them. In addition, in the drawings, the shape and the thickness of the regions are exaggerated for effective description of the technical content.

In addition, in various embodiments of the present specification, terms such as first, second, and third are used to describe various components, but these components should not be limited by these terms. These terms are only used to distinguish one component from another component. Accordingly, what is referred to as a first component in one embodiment may be referred to as a second component in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiment. In addition, in the present specification,'and/or' is used to mean including at least one of the elements listed before and after.

In the specification, expressions in the singular include plural expressions unless the context clearly indicates otherwise. In addition, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, elements, or a combination of the features described in the specification, and one or more other features, numbers, steps, and configurations It is not to be understood as excluding the possibility of the presence or addition of elements or combinations thereof. In addition, in the present specification, "connection" is used to include both indirectly connecting a plurality of constituent elements and direct connecting.

In addition, terms such as "... unit", "... group", and "module" described in the specification mean units that process at least one function or operation, which can be implemented by hardware or software or a combination of hardware and software. have.

Further, in the following description of the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

Hereinafter, a contact-type axial force measuring apparatus according to an embodiment of the present invention will be described with reference to the drawings.

1 to 3 are views for explaining a contact-type axial force measurement device according to an embodiment of the present invention, and FIGS. 4 and 5 are views for explaining an axial force measurement unit according to an embodiment of the present invention, and FIGS. 6 to 8 is a view for explaining an axial force determination unit according to an embodiment of the present invention.

Referring to FIG. 1, the contact-type axial force measuring device may include an axial force measuring unit 100 and an axial force determining unit 200.

The axial force measuring unit 100 may be fixed to one side of the body of the bolt B in a detachable manner, as shown in FIG. 2. The axial force measuring unit 100 may measure the axial force of the bolt B when a fastening force is applied to the bolt B. For example, the axial force measurement unit 100 provides data necessary for axial force measurement to the axial force determination unit 200 by measuring deformation caused by the bolt (B) according to the fastening force applied to the bolt (B). can do.

For example, the axial force measurement unit 100 is fixed between the first and second fixing objects when the bolt (B) penetrates the first fixing object and the second fixing object and is fastened with a nut Can be. Accordingly, the axial force measuring unit 100 may measure the axial force of the bolt B that changes as a fastening force is applied. Specifically, the axial force measuring unit 100 is fixed to the body of the bolt B, and as the fastening force is applied, the displacement in the longitudinal direction of the bolt B may change. At this time, the axial force measuring unit 100 may also be deformed. Accordingly, the axial force determination unit 200 may measure the axial force of the bolt B through the deformation of the axial force measurement unit 100. A detailed description of this will be described later.

When the deformation is measured by the axial force measurement unit 100, the measured deformation may be transmitted to the axial force determination unit 200.

Accordingly, the axial force determination unit 200 may determine the axial force of the bolt B based on the deformation received from the axial force measurement unit 100.

Specifically, the axial force determination unit 200, in consideration of the deformation received from the axial force measurement unit 100 and the stiffness of the bolt (B) and the axial force measurement unit 100, the bolt (B) You can judge the axial force.

The axial force determination unit 200 may predict the axial force through Equation 1 below.

<Equation 1>

Pb = (K1) X (εb)

Here, Pb may be the axial force of the bolt, K1 may be the rigidity of the bolt and the object to be fixed, and εb may be the amount of deformation in the longitudinal direction of the bolt.

In the <Equation 1>, the K1 value may be a value simulated in advance according to the bolt (B) and a fixing object fastened by the bolt (B). Accordingly, the axial force determination unit 200 may determine the Pb value, that is, the axial force, in consideration of the εb value, that is, the amount of deformation in the longitudinal direction of the bolt B.

That is, the axial force determination unit 200, since the K1 value is a predetermined value, the axial force measurement unit 100 determines the longitudinal deformation amount εb of the bolt B through the <Equation 1>. Just by measuring, it is possible to easily determine the axial force of the bolt (B).

Thus, the contact-type axial force measuring device, unlike the conventional bolt (B) axial force measurement and determination method, can measure and determine the axial force of the bolt (B) without directly attaching a sensor to the bolt (B). There is.

Therefore, the contact-type axial force measuring device is fixed to the body of the various types of bolts (B), regardless of the shape of various types of bolts (B) on the market, to facilitate the axial force of the bolts (B). Can be measured and judged properly.

Accordingly, the contact-type axial force measuring device is suitable for use in mass production sites due to its ease of use.

Hereinafter, the configuration of the axial force measuring unit 100 for measuring the longitudinal deformation amount εb of the bolt B will be described in detail.

1 and 2, the axial force measurement unit 100 includes a deformable body 110, a first deformable wing 122, a second deformable wing 124, and an opening/closing part 130. I can.

The deformable body 110 may accommodate a bolt B in the longitudinal direction therein.

Specifically, the deformable body 110 may be fixed to the body of the bolt B exposed to the outside from the bolt B.

To this end, the deformable body 110 includes a first deformable wing 122 provided on one side of the bolt B, and a first deformable wing 122 provided on the other side of the bolt B, as shown in FIG. 2. It may include two deformation wings 124.

Accordingly, the deformable body 110 may be fixed in the longitudinal direction of the bolt B by the first and second deformable blades 122 and 124.

In this case, the bolt B may fasten the first fixing object and the second fixing object through a corresponding nut. In other words, the deformable body 110 may be fixed between the first and second fixing objects.

The deformation body 110 may include a deformation detection sensor 115 on one surface. For example, the deformable body 110 is. A strain gage may be provided on one side.

Hereinafter, in the present invention, it is assumed that the strain detection sensor 115 is a strain gauge.

The deformation detection sensor 115 may detect a predetermined deformation rate when the bolt B deforms in the longitudinal direction.

Specifically, the deformation detection sensor 115, when a fastening force is applied to the bolt (B), the deformation body that is deformed as one side of the bolt (B) and the other side of the bolt (B) are deformed. (110) Strain can be detected.

That is, the deformation detection sensor 115 is provided in the deformation body 110 and may be deformed according to the deformation of the deformation body 110.

On the other hand, the deformation detection sensor 115 may be deformed in a different direction, unlike the bolt B deformed in the longitudinal direction when the fastening force is applied.

Accordingly, a linear correlation between the deformation of the bolt (b) in the longitudinal direction and the deformation of the deformation detection sensor 115 is required.

The linear correlation may be defined by the following <Equation 2>.

<Equation 2>

εb = (K2) X (εs)

Here, K2 may be a correlation coefficient, and εs may be a strain of the strain detection sensor.

According to an embodiment of the present invention, in Equation 2, the K2 value may be obtained through simulation.

Accordingly, the value of εb, that is, the amount of deformation in the longitudinal direction of the bolt, can be obtained through the εs value of Equation 2, that is, the strain rate of the sensor detected by the strain detection sensor 115.

When the εb value is obtained through <Equation 2>, the axial force of the bolt B may be determined by considering the εb value through the <Equation 1>.

That is, through <Equation 1> and <Equation 2>, it is possible to easily determine the axial force of the bolt B simply by detecting the strain rate of the sensor in the strain detection sensor 115.

According to an embodiment, the thickness of the first and second deformable blades 122 and 124 may be thinner than a pitch of the bolt B.

Accordingly, one side of the first and second deformable blades 122 and 124 may be easily fixed to the bolt B by engaging the threaded line of the bolt B.

The first and second deformable blades 122 and 124 are provided on both sides of the deformable body 110, and when a fastening force is applied to the bolt B, the first and second deformable blades (122, 124) can be transformed first.

When the first and second deformable wings 122 and 124 are deformed, the deformable body 110 may be deformed next through the deformation of the first and second deformable wings 122 and 124.

As described above, as the deformation detection sensor 115 is provided on one side of the deformation body 110, it is deformed according to the deformation of the deformation body 110, and the bolt (B) When a fastening force is applied, the first and second deformable wings 1222 and 124, the deformable body 110, and the deformation detection sensor 115 may be deformed in this order.

That is, according to an embodiment of the present invention, when a fastening force is applied to the bolt (B), the strain rates of the first and second deforming blades 122 and 124 fixed to both sides of the bolt (B), It is possible to determine the axial force of the bolt B in consideration of all the strain rates of the deformable body 110.

The linear correlation according to <Equation 1> and <Equation 2> may depend on the shape and material of the first and second deformable blades 122 and 124 and the deformable body 110. .

For example, the shape of the axial force measuring unit 100 composed of the deformable body 110 and the first and second deformable blades 122 and 124 provided on both sides of the deformable body 110 is, It may be provided in at least one of a semicircle, an oval, a siot, or a trapezoid.

In addition, the material of the first and second deformable wings 122 and 124 and the deformable body 110 may be at least one of metal, elastomer, ceramic, or wood.

The deformable body 110 may have a transmission unit TM on one side.

Accordingly, the transmission unit TM may transmit the deformation sensed by the deformation detection sensor 115.

Specifically, the transmission unit TM may transmit the deformation detected by the deformation detection sensor 115 to the reception unit RC of the axial force determination unit 200.

The deformable body 110 may further include an opening/closing part 130.

Accordingly, the deformable body 110 can easily accommodate the bolt B through the opening/closing part 130 as shown in FIG. 2.

In order to describe the opening and closing unit in more detail, referring to FIG. 3, the opening and closing unit 130 may be provided in the form of a spring-based snap-fit.

Specifically, one side of the opening and closing part 130 may be fitted into a groove formed in the first and second deformable blades 122 and 124.

In this case, the opening/closing part 130 may be formed in a spring structure.

Accordingly, the opening and closing part 130, as shown in FIG. 3, has a length of L2 before being fitted into the grooves formed in the first and second deformable blades 122 and 124, and then After being fitted into the grooves formed in the second deformable blades 122 and 124, it may have a length of L1 (here, L1> L2).

That is, the opening and closing part 130 has elasticity by being formed in the spring structure, so it can be elastically deformed before and after being fitted into the grooves formed in the first and second deforming blades 122 and 124. There is.

The axial force determination unit 200 may include a receiving unit RC.

Accordingly, the axial force determination unit 200 may receive a deformation transmitted from the transmission unit TM of the axial force measurement unit 100.

When the fastening force is applied to the bolt B, the axial force determination unit 200 may determine the axial force applied to the bolt B based on the deformation transmitted from the transmission unit TM.

In this case, the axial force determination unit 200 may acquire the deformation in real time.

Here, the deformation means including both the deformation rate of the first and second deformation blades 122 and 124 and the deformation rate of the deformation body 110 as described above, that is, when the fastening force is applied. Can be understood.

Accordingly, the axial force determination unit 200 considers a linear correlation between the strain and the amount of deformation in the longitudinal direction of the bolt B due to the fastening force applied to the bolt B, and the bolt B You can judge the axial force applied to.

The axial force determination unit 200 may obtain the linear correlation in advance before applying the fastening force.

Accordingly, when the fastening force is applied, the axial force determination unit 200 determines the axial force of the bolt B in real time in consideration of the strain obtained in real time through the previously obtained linear correlation. It can be done.

Hereinafter, the axial force measuring unit 100 will be described in more detail.

Referring to FIG. 4, the axial force measuring unit 100 may have a Digut shape before applying a fastening force to the bolt B.

Meanwhile, referring to FIG. 5, the shape of the axial force measurement unit 100 may be transformed into a trapezoidal shape after applying a fastening force to the bolt B.

This is, as described above, as the first and second deformation blades 122 and 124 provided on both sides of the deformation body 100 of the axial force measurement unit 100 are fixed to the bolt B, the fastening force This is because when applied, the axial force measuring unit 100 is deformed according to the deformation of the bolt B in the longitudinal direction.

Specifically, the axial force measurement unit 100, as a fastening force is applied to the bolt (B), the first and second deformation blades 122 and 124, the deformation body 110, the deformation detection sensor ( 115) can be modified in order.

That is, as shown in FIG. 5, when a fastening force is applied to the bolt (B), the bolt (B) is tensioned (εb) in the Z-axis direction, so that the first fixed to the bolt (B) And the second deformable wings 122 and 124 and the deformable body 110 may be deformed.

In addition, as the deformable body 110 is deformed, the deformation detection sensor 115 provided in the deformable body 110 may be deformed (εs).

Accordingly, the axial force measurement unit 100 may transmit the deformation εs of the deformation detection sensor 115 to the receiving unit RC through the transmission unit TM.

Hereinafter, the axial force determination unit 200 will be described in more detail.

Referring to FIG. 6, the axial force determination unit 200 determines the deformation εs of the deformation detection sensor 115 transmitted from the transmission unit TM of the axial force measurement unit 100, and the receiving unit RC. You can receive it through.

In this case, communication between the transmission unit TM and the reception unit RC may be performed by wire or wirelessly.

When receiving the deformation (εs) through the receiving unit (RC), the axial force determination unit 200 may determine the axial force of the bolt (B) through a linear correlation obtained in advance before applying the fastening force. have.

Among the above-described embodiments, it is assumed that the shape of the axial force measuring unit 100 is D.

When the shape of the axial force measuring unit 100 is Digut, the axial force may be predicted through <Equation 3> below.

<Equation 3>

Pb = (K1) X (K2) X (εs)

7 and 8, the K1 value may depend on the strain rate of the strain detection sensor 115 by Equation 4 below.

<Equation 4>

Δεb = [(H ³ /3I) + (H ² L/I) + (L/A)]/ [(1/hb)-(Hh/2I)] X (εs)

Here, K1 = [(H ³ /3I) + (H ² L/I) + (L/A)]/ [(1/hb)-(Hh/2I)].

In addition, the K2 value may depend on the amount of deformation in the longitudinal direction of the bolt (B) by the following <Equation 5>.

<Equation 5>

Pb = (AsEb)/ (2L) X (Δεb)

Here, K2 = (AsEb)/ (2L).

In addition, As may be a stress area that the bolt receives, and Eb may be a Young's modulus of bolt.

That is, according to the <Equation 3> to <Equation 5>, when a fastening force is applied to the bolt (B), the first and second deformable blades 122 fixed to both sides of the bolt (B) It is possible to determine the axial force of the bolt (B) in consideration of a linear correlation between the strain of 124, the strain of the deformable body 110, and the amount of strain in the longitudinal direction of the bolt (B).

As described above, the linear correlation can be obtained in advance before applying the fastening force.

Accordingly, according to an embodiment of the present invention, by receiving the deformation (εs) measured and transmitted in real time by the axial force measuring unit 100, j in real time by the axial force determining unit 200, the bolt ( The axial force of B) can be predicted in real time.

That is, when using the contact-type axial force measuring device according to an embodiment of the present invention, in the axial force determination unit 200, the strain on one side and the other side of the bolt (B), and the amount of deformation in the longitudinal direction of the bolt (B) Since the linear correlation of is obtained before applying the fastening force, when the fastening force is applied to the bolt (B), simply measuring the strain (εs) of the strain detection sensor through the axial force measurement unit 100 , It is possible to quickly and easily predict the axial force of the bolt (B).

In the above, the present invention has been described in detail using preferred embodiments, but the scope of the present invention is not limited to specific embodiments, and should be interpreted by the appended claims. In addition, those who have acquired ordinary knowledge in this technical field should understand that many modifications and variations can be made without departing from the scope of the present invention.

100: axial force measurement unit
110: deformed body
115: deformation detection sensor
122: first deformation wing
124; 2nd transformation wing
130: opening and closing part
TM: Transmitter
RC: receiver
200: axial force determination unit
B: bolt

Claims (10)

A deformable body in which the bolt penetrates in the longitudinal direction;
A first deformable blade provided on one side of the deformable body and fixed to one side of the bolt;
A second deformable blade provided on the other side of the deformable body and fixed to the other side of the bolt;
A deformation detection sensor provided on one side of the deformable body and detecting a deformation rate of one side of the bolt and the other side of the bolt; And
Including; an axial force determination unit for determining an axial force applied to the bolt based on a strain detected by the deformation detection sensor by a fastening force applied to the bolt,
The axial force determination unit,
Predict the axial force of the bolt according to the following <Equation 1> and <Equation 2>,
Considering a linear correlation between the deformation rate of the deformation detection sensor according to the following <Equation 2> and the amount of deformation in the longitudinal direction of the bolt due to the fastening force applied to the bolt, the length of the bolt according to the following <Equation 1> A linear correlation between the amount of directional deformation and the axial force applied to the bolt is obtained before applying the fastening force,
A contact-type axial force measuring device for predicting the axial force of the bolt only by measuring the strain of the strain detection sensor according to the following <Equation 2>.
<Equation 1>
Pb = (K1) X (εb)
<Equation 2>
εb = (K2) X (εs)
(Here, Pb is the axial force of the bolt, K1 is the stiffness of the bolt and the object to be fixed, εb is the amount of deformation in the longitudinal direction of the bolt, K2 is the correlation coefficient, and εs is the strain of the strain detection sensor)
delete The method of claim 1,
The linear correlation is,
The contact-type axial force measuring device, depending on the shape and material of the first and second deformable blades and the deformable body.
The method of claim 1,
The deformable body,
The contact-type axial force measuring device is fixed to the bolt body exposed from the bolt to the outside by the first and second deformable blades.
The method of claim 4,
The bolt,
A contact-type axial force measuring device for fastening the first fixing object and the second fixing object through a corresponding nut.
The method of claim 5,
The deformable body,
A contact-type axial force measuring device fixed between the first and second fixed objects.
The method of claim 1,
The deformable body,
A contact-type axial force measuring device that is fixed in the longitudinal direction of the bolt by the first and second deformable blades.
The method of claim 1,
The deformation according to the fastening force applied to the bolt,
A contact-type axial force measuring device for deforming the deformation detection sensor through the first and second deformation blades, through the deformation body.
The method of claim 1,
The thickness of the first and second deformation blades,
Thinner than the pitch (pitch) of the bolt, contact-type axial force measuring device.
The method of claim 1,
The deformable body,
The contact-type axial force measuring device further comprises an opening and closing part so that the bolt can be accommodated into the inside of the deformable body.

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