JP2019132841A - Fastening force detection device - Google Patents

Abstract

To provide a detection device capable of detecting a state (fastening strength) of fastening force without compressing sensors with fastening means.SOLUTION: A fastening strength detection device 1 includes an insertion section 21 for inserting a shaft section 71 of fastening means 7 therein and is used in addition to a washer or instead of the washer. The fastening strength detection device includes: a fastening force transmission section 2 which is formed into a cylindrical shape by a wall surface of proper thickness while forming the insertion section and transmits fastening force by the fastening means; and a plurality of partition wall sections 3 which constitute plate-like members of proper thickness which are radially extended from the wall surface of the fastening force transmission section and are capable of transmitting the fastening force together with the fastening force transmission section. Strain sensors are installed in one or both of the wall surface of the fastening force transmission section and the surfaces of the partition wall sections.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus for detecting a fastening force when fastened by fastening means formed by bolts and nuts.

  Generally, fastening by fastening means such as bolts and nuts is used to fix a material to be fastened, but the fixed state thereof is determined by the degree of fastening force. Moreover, even if it is once fastened and fixed, the fastening state may also change due to environmental changes that occur during the long-term fastening state. For example, the fastening material may vibrate due to vibration of the fastening material, and the fastening force may gradually decrease as the fastening means repeatedly expands and contracts due to temperature changes. . Further, the fastening force may be reduced by corrosion or cracking in the bolt.

  In view of the above circumstances, a method for detecting the strength of fastening force (particularly the occurrence of looseness) has been proposed. As means for detecting the looseness of the fastening force, the pressure acting exclusively between the bolt head and the fastening material is measured (see Patent Document 1), or two fastening materials are fastened. There has been a technique (see Patent Document 2) that measures a pressure acting between two fastening materials when fastened by means. In these conventional techniques, the above-described pressure drop causes looseness to occur, and a piezoelectric element has been used for the pressure measurement.

JP 60-39523 A JP-A-5-52684 JP 2014-228465 A

  However, the configuration disclosed in the above two documents is to sandwich a piezoelectric element between the fastening member and the fastening material or between the fastening materials, respectively. There is concern about a decrease in fastening force due to deformation, and since a strong fastening force acts on the piezoelectric element, there are concerns about durability in the case of long-term use. Furthermore, since the bolts or nuts need to be processed for sensor installation, there was concern about their strength reduction. Therefore, by arranging a pressure-sensitive sensor inside the mounting bracket, an apparatus has been developed that detects the state of the fastening force without directly sandwiching the piezoelectric element between the fastening member or the fastening material. (See Patent Document 3).

  The invention with the above configuration uses a pressure-sensitive sensor in which conductive particles such as metal are mixed in a rubber (or elastomer) insulator. This pressure-sensitive sensor is disposed inside the mounting bracket. By laminating the electrodes between the two electrodes, the conductive particles function as an insulating material because they are dispersed in a state where no pressure is applied. However, when pressure is applied, the conductive particles are contacted by compressive deformation. Thus, the conductive material is changed. Further, since the electric resistance value changes according to the degree of the compression deformation, the fastening force can be calculated by analyzing the resistance value. Therefore, the loose state of the fastening means can be measured steplessly.

  However, in the invention with the above configuration, since the fastening means fastens and fixes the material to be fastened via the mounting bracket, even if the mounting bracket does not deform, Therefore, it is necessary to compress and deform at least the pressure sensitive sensor. For this reason, the detection of the fastening force is due to the compression deformation of the pressure sensor, so that the deformation of the pressure sensor continues while the fastening force is acting in a loose state. Concerns about durability were raised. Furthermore, there is a concern that the fastening material may be fastened and fixed via the pressure sensor if the compressive deformation of the pressure sensor causes a change over time.

  The present invention has been made in view of the above points, and its object is to detect a state of fastening force (fastening strength) without compressing sensors by fastening means. Is to provide.

  Accordingly, the present invention is a fastening strength detecting device that has an insertion portion for inserting the shaft portion of the fastening means and is used in addition to or in place of the washer, while forming the insertion portion. A fastening force transmitting portion that is formed in a cylindrical shape by a wall surface having an appropriate thickness and transmits a fastening force by the fastening means, and a plate member having an appropriate thickness that extends radially from the wall surface of the fastening force transmission portion. And a plurality of partition walls that can transmit the fastening force together with the fastening force transmission part, and a strain sensor installed on either or both of the wall surface of the fastening force transmission part and the surface of the partition part. It is characterized by providing.

  According to the above configuration, the fastening force to be applied by the fastening means acts in a distributed manner on the fastening force transmission portion and the partition wall portion, and can be transmitted to the fastening material through these. At this time, the fastening force transmitting portion and the partition wall portion have an appropriate thickness, so that the fastening force to be transmitted can be applied to the fastening material without being attenuated. In addition, since the fastening force is detected by a strain sensor provided on the wall surface of the fastening force transmitting portion or the surface of the partition wall, it is possible to calculate the compressive stress (fastening force) from the measured value of the compressive strain. Become. It is also possible to detect the state of the fastening force acting evenly in the axial direction by installing strain sensors at multiple locations of the fastening force transmission part or by installing multiple strain sensors on the surface of the plurality of partition walls. It becomes possible.

  In the invention with the above-described configuration, the partition wall portion forms a plurality of gap portions between the adjacent partition wall portions, and is installed in one of the gap portions to supply power to the strain sensor. It can be set as the structure provided with a power supply.

  According to the above configuration, the plurality of voids are formed by the wall surface portion extending radially from the cylindrical fastening force transmission portion, and the gap portion is formed by at least the fastening force transmission portion and the partition wall. Therefore, the power source can be installed in the gap. Since this power supply supplies power necessary for operation to the strain sensor, power can be supplied individually for each fastening strength detection device (that is, for each fastening means), and this power supply can be continued. For example, continuous measurement using a strain sensor is possible. The power supply necessary for the operation of the strain sensor means power supply to the control circuit of the sensor, but when a strain gauge is used as the strain sensor, it is provided for voltage application to the circuit constituting the strain gauge. It means that.

  In the case of the invention with the above configuration, a detection unit that detects the output value of the strain sensor and a transmission unit for transmitting the detection value are provided in any one of the gaps, and the detection unit and the transmission The unit may be connected to the power source or installed with the power source in a state of being connected to another power source.

  According to the said structure, after detecting the distortion amount (detection value) output from a distortion sensor, the detected value can be transmitted outside. The power supply supplies power necessary for the operation of the strain sensor and can also function as a power supply for the operation of the detection unit and the transmission unit. Can individually supply power to the detection unit and the transmission unit. These installation locations are any of the gaps, and in addition to the installation in one place, they may be divided into a plurality of gaps, depending on the size of the gap and the size of the installation. It will be judged.

  In each invention of the above configuration, it is formed in a substantially annular shape so as to simultaneously contact the end surfaces of the fastening force transmission part and the partition part, and is disposed on both sides in the direction in which the fastening force by the fastening means acts. It can be set as the structure further provided with two fastening contact parts.

  According to the above configuration, since the end surfaces of the fastening force transmission part and the partition part are brought into contact with the fastening contact part on both sides where the fastening force acts, one fastening contact part is formed by the fastening means. The fastening force is dispersed and transmitted to the fastening force transmission part and the partition part, and the other fastening contact part transmits the fastening force transmitted by the fastening force transmission part and the partition part to the material to be fastened. It becomes. Accordingly, the fastening force acts on both the fastening force transmission portion and the partition wall portion, so that the load can be dispersed and the strength that can withstand the fastening force can be maintained.

  In the case of the above configuration, at least one of the fastening contact portions may be formed integrally with the fastening force transmission portion and the partition wall portion.

  According to the above configuration, since the fastening contact portion is formed integrally with the fastening force transmission portion and the partition wall portion, the space portion formed by the partition wall portion has a bottom surface portion or a top plate portion (or both). Thus, the above-described power source and the like can be installed in advance on these bottom surface portions and the like.

  In the present invention having the above-described fastening contact portion, the fastening contact portion is a wall surface of the fastening transmission portion in a region not subjected to contact by the fastening force transmission portion or the partition wall portion. Alternatively, a strain sensor may be installed instead of or in addition to the strain sensor installed on the surface of the partition wall. In addition, in the case of a configuration in which a power source is installed in any of the gaps formed between adjacent partition walls, a configuration in which power is supplied from the power source can be employed.

  According to the above configuration, the fastening contact portion disperses the fastening force by the fastening means, and naturally the fastening force acts, so that the fastening contact portion itself may be distorted. If the strain level can be measured effectively, a tightening force intensity can be measured by providing a strain sensor at the tightening contact portion. Therefore, in addition to measuring the strain at the tightening contact only and detecting changes in the tightening force strength, the strain at the tightening contact is measured in addition to the tightening force transmission and the strain at the bulkhead. Thus, it is possible to detect the change state of the fastening force. The strain at the tightening contact portion can be calculated as a tightening force based on the tensile stress (elongation) or shear stress (deflection) of the surface.

  Furthermore, in the invention of each configuration described above, a closing wall for enclosing the gap portion may be provided between the outer end portions of the adjacent partition walls.

  According to the above configuration, in the state of being fastened by the fastening means, the periphery thereof, particularly the periphery of the gap portion, can be closed from the outside, and the outside of the power supply etc. installed in the gap is suppressed while being separated from the outside. Invasion of insects and contamination of parts can be eliminated. In particular, in the case of the configuration in which the fastening contact portion is provided, a space state in which the gap portion is closed can be obtained, and a shielding effect from the outside can be obtained.

  In the invention of each configuration described above, when the fastening means is used together with a washer, the outer periphery of the fastening force transmitting portion has a smaller diameter than the outer periphery of the washer, and the outer end portion of the partition wall portion is the washer. It is preferable that it protrudes outward rather than the outer periphery.

  In the case of the above configuration, when a washer is used when the fastening means is used, the fastening force is first transmitted through the washer. Therefore, the fastening force transmission portion is more than the outer periphery (outer diameter) of the washer. By reducing the outer periphery (outer diameter) of the belt, the fastening force can be concentrated on the fastening force transmission portion. At this time, by providing a strain sensor on the wall surface of the fastening force transmission unit, the strain amount can be measured as a measurement value of the concentrated pressure. In addition, by making the outer end of the partition wall outward from the outer periphery of the washer, the fastening force transmitted through the washer can be distributed to the partition wall, so that the fastening force is concentrated on the fastening force transmission unit. However, it is possible to disperse appropriately and maintain the strength that can withstand the fastening force. In particular, in the configuration having the fastening contact portion, the fastening contact portion has a larger area than the washer, so that the fastening force acting on the washer can be dispersed through the fastening contact portion. it can.

  In the invention having the above-described configuration, the partition wall includes end surface portions orthogonal to the action direction on both sides of the action direction of the fastening force by the fastening means, the total area of the one end face portion, and the fastening force transmission portion. It is preferable that the sum of the total area and the end face area be larger than the area of the one side surface of the washer to be used.

  According to the above configuration, when the fastening force is applied via the washer, the load can be transmitted by an area larger than the surface of the washer, and the stress applied to the fastening force transmission unit and the partition wall by the load is reduced. be able to. In particular, in the case of a configuration in which a fastening contact portion is provided, the stress acting on the fastening force transmitting portion and the partition wall portion can be reduced and durability can be improved because the end surface can be dispersed. it can.

  According to the present invention, the fastening force transmitting portion and the partition wall portion have sufficient durability, and the strain amount generated in the member when this is transmitted to the fastening material is detected by the strain sensor. The sensors are not compressed by the fastening force. The same applies when the strain sensor is installed at the fastening contact portion. Further, since the strain amount in either one or both of the fastening force transmission portion and the partition wall portion is detected, and in addition to or in addition to this, the strain amount in the fastening contact portion is detected. The fastening force can be easily calculated from the amount of strain, and since the measurement is performed at a portion where the fastening force is continuously applied, continuous fastening strength can be detected. By transmitting these detection values from the transmission unit, transmission data can be received by a specific management device, and the state of fastening strength can be centrally managed. At this time, if the surrounding environment information such as temperature, humidity or vibration amount at the installation location can be input at the same time, specify the causal relationship with the surrounding environment as the cause of loosening of the fastening means. It can also be used.

It is explanatory drawing which shows the outline | summary of the 1st Embodiment of this invention. It is explanatory drawing which shows the state in planar view of 1st Embodiment. It is explanatory drawing which shows the usage condition of 1st Embodiment. It is explanatory drawing which shows the usage condition of 1st Embodiment. It is explanatory drawing which shows the outline | summary of 2nd Embodiment. It is explanatory drawing which shows the state in planar view of 2nd Embodiment. It is explanatory drawing which shows the outline | summary of the modification 1 of 2nd Embodiment. It is explanatory drawing which shows the outline | summary of the modification 2 of 2nd Embodiment. It is explanatory drawing which shows the outline | summary of the other modification of 2nd Embodiment. It is explanatory drawing which shows the outline | summary of other embodiment of this invention. It is explanatory drawing which shows the usage condition of a fastening intensity | strength detection apparatus. It is explanatory drawing which shows the modification in the usage condition of 1st Embodiment.

<First Embodiment>
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an outline of a fastening strength detecting apparatus according to a first embodiment of the present invention. The fastening strength detection device 1 of the present embodiment is configured by a fastening force transmission portion 2 and a plurality (six in the figure) of partition walls 3 extending radially from the fastening force transmission portion 2. .

  The fastening force transmitting portion 2 is provided with an insertion portion (through hole) 21 in the center, and allows fastening means (for example, a shaft portion of a bolt) to be inserted. Further, it is formed in a cylindrical shape (cylindrical shape) having a sufficient width dimension W1, and maintains an area capable of sufficiently contacting with the fastening means or the like (clamping force can be transmitted). Further, the thickness H1 in the direction (length direction) in which the fastening force acts is configured to be sufficiently smaller than the width dimension W1, and does not buckle due to the action of the fastening force (compression force).

  The partition walls 3 are formed integrally with the fastening force transmission unit 2, and adjacent partition walls 3 are distributed at equal intervals (the same central angle). It is configured with a thickness H2 in the same height direction in the direction in which the fastening force acts, and the width dimension W2 of each partition wall portion 3 is set to have a sufficiently abuttable area. The partition wall portion 3 has a function of transmitting the fastening force together with the fastening force transmission portion 2 in addition to the function of forming the gap portion 4 between the partition wall portions 3 and the adjacent partition wall portion 3. While having an area, the thickness H2 is made sufficiently smaller than the width dimension W2 so as not to buckle.

  The said structure can be provided by the method of cutting out a flat member to a predetermined shape (cylindrical shape and radial shape), or press work. Since both 2 and 3 have the same height, when the fastening means is a bolt and a nut, it is possible to simultaneously contact these fastening surfaces, and the fastening force by the fastening means can be reduced. It can be supported (transmitted) while being dispersed. When the fastening means uses a washer, the compression force dispersed by the washer is further dispersed by both.

  The drawing further shows that the fastening contact portions 10a and 10b are arranged in the direction in which the fastening force acts (vertical direction), respectively, and a bolt head or a washer is applied to the fastening contact portions 10a and 10b. By making contact, all of the acting compressive force (fastening force) is applied to the fastening contact portions 10a and 10b and can be dispersed in the fastening force transmitting portion 2 and the partition wall portion 3. The fastening contact portions 10a and 10b are members each having a substantially annular shape with an appropriate thickness. In the center, the insertion portions (through holes) 11a and 11b having the same diameter as the fastening force transmission portion 2 are provided. Is provided so that the fastening means can be inserted. By configuring the outer diameters of the tightening contact portions 10a and 10b to be larger than the outer diameter of the tightening force transmitting portion 2, the end surfaces of the tightening force transmitting portion 2 and the partition wall portion 3 are connected to the tightening contact portions 10a and 10b. The same surface is brought into contact with 10b at the same time. With such a configuration, the fastening contact portion 10b that receives the fastening force of the fastening means disperses the fastening force, and the other fastening contact portion 10a transmits from the fastening force transmission portion 2 and the partition wall portion 3. The tightening force to be transmitted is distributed to the material to be fastened. In addition, a substantially annular shape means that the outer edge shape includes a circular shape or other polygonal shapes, and includes a case where the outer peripheral shape is not continuous in the annular circumferential direction (having a cut portion in the radial direction).

  By the way, as shown in FIG. 2A, since the partition wall 3 is radially extended from the cylindrical fastening force transmitting portion 2 disposed in the center, between the adjacent partition walls 3, A plurality of gaps 4 are formed respectively. For example, a power source or the like (the figure illustrates a button battery) 5 can be arranged by using the gap 4. Further, since the wall surface 22 of the fastening force transmitting portion 2 or the surface 31 of the partition wall portion 3 is exposed to the outside through the gap portion 4, the surfaces 22 and 31 are strained. The sensors 6a and 6b can be attached.

  The strain sensors 6a and 6b are provided to measure the amount of strain due to the compressive force applied to the fastening force transmitting portion 2 or the partition wall portion 3, and either one or both of them can be used. Which form is selected can be determined by whether or not the fastening force acts on them. When the tightening force is concentrated only on the tightening force transmitting portion 2, the strain sensor 6a should be provided only on the tightening force transmitting portion 2, and when the tightening force is transmitted to both sides, the strain sensors 6a and 6b are provided on both sides. Or the strain sensor 6b can be provided only in the partition wall 3. Moreover, it is preferable to install a plurality of strain sensors 6a and 6b instead of only one place. For example, the strain amount corresponding to the compressive force acting on the whole can be measured by providing it at two or six symmetrical positions about the axis of the insertion portion (through hole) 21. For example, this can be a material for determining whether or not the entire tightening force is acting properly when the tightening force by the tightening means is acting on the axis.

  In addition, if the operating state of the fastening force is measured in either the fastening force transmission part 2 or the partition wall part 3, it is possible to detect the change in the state. It is also possible to detect the entire deformation amount of the intensity detection apparatus 1 and verify the intensity of the apparatus.

  Such a fastening force transmission part 2 and the partition wall part 3 are configured to have a plane (end face) having an appropriate area in plan view (the same applies to bottom view), and the fastening force applied by the fastening means is applied to these planes. It is set as the structure which can support (transmit). Therefore, the area of each plane needs to be such that the fastening force can be transmitted. For example, when bolts and nuts are used as fastening means, and when a washer is not used, the flat surface of the fastening force transmission portion 2 is the contact surface of the bolt head (excluding the shaft portion on the shaft portion side). It is preferable to make it the same level. This is because the fastening force by the bolts is concentrated on the fastening force transmission unit 2. In this case, the partition wall 3 functions as a reinforcing member for maintaining the standing state of the fastening force transmitting portion 2.

  On the other hand, when it is assumed that a washer is used, the outer periphery of the fastening force transmitting portion 2 is smaller in diameter than the outer periphery of the region (virtual circle in the figure) P with which the washer abuts, as shown in FIG. In addition, the tip end (outer end portion) of the partition wall portion 3 is extended with a length that extends outward from the region P. This is to further disperse the fastening force transmitting portion 2 and the partition wall portion 3 in which the fastening force is dispersed by the washer. In such a configuration, the partition wall 3 also exhibits a function of transmitting the fastening force. In this case, the total area of both the fastening force transmitting portion 2 and each plane (end surface) of the partition wall portion 3 is made larger than the area of the region P where the washer abuts, thereby reducing the fastening force transmitted to the washer. It can be dispersed.

  The fastening strength detection device 1 having the above-described configuration can be used like a washer for the fastening means. FIGS. 3A and 3B show the usage state. FIG. 3A shows a state before the fastening strength detecting device 1 is mounted on the shaft portion 71 of the bolt 7, and FIG. The state which mounted | wore the intensity | strength detection apparatus 1 is shown. Note that the fastening strength detection device 1 shown in the figure is illustrated as being integrated with the fastening contact portions 10a and 10b arranged above and below, but the fastening strength detection device 1 may be used alone. Good. Further, as a fastening means, a case where a bolt 7 and a nut 8 are used and a washer 9 is used is illustrated.

  When detecting the fastening strength by such fastening means 7, 8, the bolt 7 is inserted into the insertion portion (through hole) 21 formed at the center of the integrated fastening strength detection device 1 as shown in the figure. By inserting the shaft portion 71, the shaft portion 71 can be attached in a bowl shape. In this state, it can be used like a washer by moving it to the head 72 of the bolt 7. By using the nut 8 screwed to the bolt 7 for fastening, the material to be fastened arranged in the middle can be fastened from both sides.

  The relationship with the material to be fastened is shown in FIG. The figure shows a state in which two fastening materials A and B are joined, for example, a state in which the installation member A is joined to the material B of the base portion. As shown in FIG. 4A, the fastening materials A and B are previously provided with through holes Aa and Ba through which the shaft portions 71 of the bolts 7 or the like can be inserted. Bolts or the like are provided in the through holes Aa and Ba. 7 is inserted through the shaft portion 71 and screwed with a nut or the like 8 on the tip side. Then, by rotating (tightening) the head 72 of the bolt 7 or the like, the distance between the head 72 and the nut 8 or the like is reduced, thereby applying a fastening force.

  At this time, the fastening strength detecting device 1 is disposed on the surface side of one of the fastened members A and is disposed between the head 72 of the bolt 7 or the like (a washer 9 when the washer 9 is used). Become. Accordingly, the fastening strength detection device 1 is in a state where a fastening force by a bolt 7 or the like is applied. Therefore, the fastening force transmitting portion 2 and the partition wall portion 3 constituting the fastening strength detecting device 1 receive the action of the fastening force and transmit this to the fastened member A. Therefore, the strength of the fastening force can be detected by measuring the amount of strain in either one or both of the fastening force transmitting portion 2 and the partition wall portion 3.

  The fastening force strength is detected by using the strain sensors 6a and 6b. For example, a general strain gauge can be used as the strain sensors 6a and 6b. When a strain gauge is used, a fastening strength can be calculated from an output voltage obtained by applying a voltage to a circuit constituting the strain gauge and changing a resistance value accompanying deformation of the strain gauge. The power source or the like (button battery or the like) 5 is used for voltage application in this case.

  The fastening force can be detected from the amount of strain detected by using a pressure-sensitive sensor or other strain sensor, not only when using a strain gauge. That is, the fastening force acts as a compressive force on the fastening force transmission part 2 or the partition wall part 3, so the strain amount is measured from the amount of change in the thickness H1, H2 (FIG. 1) in the height direction, and this is used as the fastening force. The magnitude of the compressive stress (fastening force) can be detected according to the stress characteristic represented by the stress-strain curve for the material of the transmission part 2 or the partition part 3.

  By the method as described above, the fastening strength can be detected by the fastening strength detection device 1 according to the present embodiment. In FIG. 4A, the fastening strength detecting device 1 is arranged on the head 72 side of the bolt 7 or the like, but as shown in FIG. You may arrange | position between the nut 8 and the material A to be fastened. Further, the nut 8 is not essential for fastening, and if a female screw is engraved on the material to be fastened, it may be directly screwed into the female screw. Furthermore, in the case of the configuration in which the fastening contact portions 10a and 10b are provided as shown in the drawing, a configuration in which the washer 9 is not used may be used.

  Since the present embodiment has the above-described configuration, the fastening force transmitting portion 2 and the partition wall portion 3 transmit the fastening force to the fastening materials A and B. Therefore, the fastening means 7 and 8 and the fastening material A , B, no sensors are interposed, and there is no need to compress the sensors with a fastening force. This eliminates the need to consider the durability of the sensors. Further, since the strain amount is detected by the fastening force transmitting portion 2 or the partition portion 3 using a strain sensor, the change in the strain amount can be continuously measured, and the state of change in the fastening strength is detected. It is also possible.

  Further, in the fastening strength detection device 1, a plurality of gaps 4 are formed by the plurality of partition walls 3, and thus other devices can be installed in the gaps 4. As the power source 5 as described above, in addition to the power source (button battery) described above, there are processing units such as a detection unit and a transmission unit, and these can be installed in the gap 4. The processing unit includes a detection processing unit (detection unit) that detects values (detection values) from the strain sensors 6a and 6b, and a transmitter (transmission unit) in addition to the processing unit that converts the detection values into output data. It is possible to transmit a detection value (output data) that can be detected by the strain sensors 6a and 6b to a predetermined management device. In addition to the illustrated button battery, the power source can be appropriately selected from a coin battery, a small lithium ion battery, and the like, and any other power source that can be stored in the gap 4 can be used. .

  The power source 5 and the like, the strain sensors 6a and 6b, the processing unit, and the like as described above can be installed by selecting any one of the gaps 4. That is, the size of the gap 4 depends on the number of partition walls 3 and the width dimension W2, and therefore, when a relatively wide space is formed, the power source 5 or the like is connected to one gap. 4 may be installed separately, but may be individually installed when the space is relatively narrow. In particular, when the strain sensors 6a and 6b are constituted by strain gauges, they can be formed in a thin film shape, so that they can be installed in the same gap 4 as other members (button batteries, etc.), and a plurality of them are installed. An individual button battery or the like may be installed in the same gap 4 for each individual strain sensor 6a, 6b. Furthermore, for the processing unit (detection unit and transmission unit), either the same gap 4 or a different gap 4 can be selected, and a button battery or the like for individually supplying power to this processing unit is installed. May be.

<Second Embodiment>
Next, a second embodiment of the present invention will be described. FIG. 5 shows a second embodiment. As shown in this figure, the fastening strength detection device 1 of the present embodiment does not make the width dimension W2 of the plurality of partition walls 3 provided radially from the fastening force transmission unit 2 constant, and the fastening force transmission unit 2 The maximum width dimension W2-1 is formed at a position to be a boundary (base side end part 30a of the partition wall part 3), and the taper shape is formed by gradually reducing the width dimension toward the outer end part 30b. Is. Accordingly, the outer end 30b of the partition wall 3 has a pointed shape.

  In addition, the base side end portion 30a of the partition wall portion 3 in the present embodiment is in contact with the adjacent partition wall portions 3, and between the partition wall portions 3, the wall surface of the fastening force transmitting portion 2 is the partition wall portion. It is not clearly distinguished from the three wall surfaces 31. Therefore, as a result, the fastening force transmission portion 2 is not formed in a cylindrical shape, but is integrated with the partition wall portion 3, and the fastening force transmission portion 2 is constituted by a portion where the base portion of the partition wall portion 3 is continuous. Is. Therefore, as a whole, a star shape having an insertion portion (through hole) 21 at the center is formed.

  In this case, as the installation location of the strain sensors 6a and 6b, the wall surface of the fastening force transmission part 2 is not selected, and the side 31 of the partition wall part 3 is near the fastening force transmission part 2 or near the tip. Or, it will be selected between them.

  In the case of the above configuration, in the vicinity of the outer end 30b of the partition wall portion 3, the width dimension W2-2 of the partition wall portion 3 is extremely small, so that the strain when the fastening force acts is small. It becomes relatively large. Therefore, by installing the strain sensor 6c in the vicinity of the outer end 30b, it becomes easy to detect a change in the strain amount. In consideration of the fact that the change in strain accompanying the decrease in the fastening strength due to the fastening means cannot be detected only at the outer end 30b, strain sensors 6a and 6b are also installed at other positions. The fastening strength can be detected by changing the amount of distortion.

  By the way, the partition part 3 in this embodiment forms the space | gap part 4 between the adjacent partition parts 3 similarly to 1st Embodiment. Accordingly, the partition wall 3 has a function of transmitting the fastening force together with the fastening force transmitting portion 2 and also has a function of forming the gap 4. Therefore, a power source or the like (button battery) 5 can be installed in the gap 4. Furthermore, it is also possible to install a processing unit such as a detection unit or a transmission unit in the gap 4 where the power source or the like (button battery) 5 is installed or in the gap 4 which is different from the power source or the like (button battery) 5. is there.

  Therefore, by providing substantially annular fastening contact portions 10a and 10b, it is possible to install a power source 5 such as a button battery or a processing portion therebetween. That is, as shown in FIG. 6 (a), since the plurality of partition walls 3 in the present embodiment are all radially extended with the same length, the outer end 30b of the partition wall 3 is an insertion portion. It will be located concentrically with the (through hole). Therefore, if the outer peripheral circle Q of the fastening contact portions 10a and 10b is a circle having a diameter that is the same as or larger than the circle (virtual circle) R that is inscribed in all the outer end portions 30b of the partition wall portion 3, These batteries 5 (button battery 51 and processing part 52 etc.) can be installed between the surfaces where the fastening contact portions 10a, 10b positioned in the vertical direction of the gap 4 face each other.

  On the other hand, as shown in FIG. 6 (b), when assuming the use of a washer, the base side end 30a of the partition wall 3 is more than the region (virtual circle in the figure) P where the washer abuts. The outer end 30b of the partition wall 3 can be positioned in the center, but the outer area 30b of the partition wall 3 is positioned outward from the virtual circle P, so that the total area of the surfaces (end surfaces) of the fastening force transmission unit 2 and the partition wall 3 The fastening force transmitted from the washer is moderately dispersed.

  Since the present embodiment is configured as described above, it is possible to transmit the fastening force by the partition wall portion 3 and to form the gap portion 4 having an appropriate space therebetween as in the first embodiment. It is the same. In addition, in the present embodiment, since the partition wall portion 3 has a tapered shape in plan view, the width dimension W2-2 in the vicinity of the outer end portion 30b can be reduced. Since the change in the strain amount by the strain sensor 6c can be detected in the vicinity of the outer end 30b due to the small width dimension W2-2, the change in the entire fastening force can be detected in a relatively detailed manner.

<Modification Example 1 of Second Embodiment>
The said 2nd Embodiment changes the structure of the partition part 3 in 1st Embodiment, The width dimension of the partition part 3 does not need to be uniform. Therefore, from the purpose of the same configuration, as shown in FIG. 7, the base side end 30a of the partition wall 3 may be curved, and the outer end 30b may be arcuate rather than pointed. The side part of the partition part 3 does not need to be a straight line, and may have a suitably curved shape. Also in this case, the partition wall 3 has a function of forming the gap 4 in addition to the function of transmitting the fastening force together with the fastening force transmitting portion 2. Therefore, by providing the substantially annular fastening contact portions 10a and 10b, it is possible to install these power sources 5 (button battery 51 and processing portion 52) between them. In this case, the diameter of the outer peripheral circle Q of the fastening contact portions 10 a and 10 b may be equal to or larger than the diameter of the virtual circle R of the outer end portion 30 b of the partition wall portion 3.

<Modification 2 of the second embodiment>
As a second modification, as shown in FIG. 8, a cylindrical shape is formed along the outer peripheral edge of one of the fastening contact portions 10a and 10b (the lower fastening contact portion 10a in the figure). The closing wall 10c is integrally formed. The closing wall 10c is an outer side of the gap 4 formed between the partition walls 3 when the fastening strength detecting device 1 having the above-described configuration is arranged between the fastening contact portions 10a and 10b. Is a wall surface member for forming a space in which the gap 4 is closed. By providing the closing wall 10c integrally with the fastening contact portion 10a in advance, the closing wall 10c becomes like a container formed in a bottomed cylindrical shape, and the fastening strength detecting device 1 is placed therein. By storing, the gap 4 is closed.

  By the way, as described above, the diameter of the outer peripheral circle of the fastening contact portion 10a may be approximately the same as or larger than the virtual circle passing through the outer end portion 30b of the partition wall portion 3. Therefore, when the diameter of the outer periphery circle of the fastening contact portion 10a is large, the outer end 30b of the partition wall portion 3 does not reach the closing wall 10c. In a strict sense, this state is not a state in which the gap portion 4 is closed, but if it is closed to surround the power source 5 (button battery 51 and processing portion 52 etc.) installed in the gap portion 4, This level is sufficient. In addition, since an appropriate gap is formed between the outer end 30b of the partition wall 3 and the closing wall 10c, a plurality of power supplies 5 (for example, button batteries 51 and It is possible to connect the processing units 52 and the like, and to install necessary devices separately in the plurality of gaps 4 so that they can be connected. For this reason, the inner wall diameter of the closing wall 10c can be increased (so that the partition wall 3 does not reach) so as to form the gap.

<Other Modifications of Second Embodiment>
As another modified example, as shown in FIGS. 9A and 9B, partition portions 3 having different forms are mixed. For example, in FIG. 9A, the partition wall portion 3 has a part of the width dimension W2a different from the other width dimension W2b. This is because, in the case of the tapered partition wall portion 3 in the second embodiment, the width dimension is small in the vicinity of the outer end portion 30b. Therefore, the strain amount is changed by installing a strain sensor in this portion. This is based on the fact that it has become easier to detect. That is, since the partition wall portion 3 transmits the fastening force together with the fastening force transmission portion 2, it is required that the change in the strain amount can be detected while maintaining a suitable strength by setting an appropriate width dimension. Therefore, a mixture of the wide partition wall 3 and the narrow partition wall 3 contributes to both requests.

  Similarly, as shown in FIG. 9B, while some of the partition walls 3a have the same configuration as that of the first embodiment, the other partition walls 3b are similar to those of the second embodiment. Tapered shape. In this case, since the cylindrical portion of the fastening force transmitting portion 2 can be formed, a strain sensor can be provided on the wall surface 22 thereof, and the strain sensor can also be provided in the vicinity of the outer end portion 30b of the tapered partition wall portion 3b. 6c can be installed, and a change in the overall fastening force can be detected at each position, so that a detection for comprehensively determining the state of the fastening force strength can be performed.

  In the case of a configuration in which partition portions 3a and 3b having different shapes are mixed as in this type of modification, in order to transmit the tightening force in a stable state together with the tightening force transmitting portion 2, they are arranged in a balanced manner. It is necessary. Therefore, in this modified example, both 3a and 3b are alternately arranged, and the radial center lines of the adjacent partition walls 3a and 3b are arranged to be equiangular and others. With such an arrangement, the entire circular end face can receive and transmit the fastening force without being biased.

<Other embodiments>
Next, another embodiment will be described. FIG. 10 shows another embodiment of the present invention. FIG. 10A shows a structure in which one fastening contact portion 10a is integrally formed as a bottom surface portion with respect to the fastening force transmission portion 2 and the partition wall portion 3, and FIG. The fastening contact portion 10b is integrally configured as a top plate portion. These integrations can be integrally configured by bonding, crimping, or welding individual members, and the integrated structure with the bottom surface portion 10a in FIG. It can also be provided.

  Thus, when one fastening contact part 10a is comprised integrally, it is good also as a form which provides the distortion sensor 6c in the said fastening contact part 10a. In other words, the fastening contact portion 10a is distorted in accordance with the fastening force acting on the fastening force transmitting portion 2 and the partition wall portion 3, so that the strain is detected using a relatively wide surface. It can be. Even in the strain measurement in such a form, it is possible to detect the fastening force acting evenly by installing the strain sensors 6c at a plurality of locations. In the case of an integral configuration, strain is generated as a whole. Therefore, by providing the strain sensor 6c at an appropriate position on the contact surface, the strain can be easily measured. Even if it is comprised as a member of, it can be set as the same form. In other words, even if it is not integral, the fastening force acts on these fastening contact portions 10a and 10b, and the fastening contact portions 10a and 10b are distorted due to the action of the fastening force. It becomes. Therefore, by providing the strain sensor 6c in a region that is not subjected to the contact of the fastening force transmission part 2 and the partition wall part 3, it is possible to detect the fastening force intensity by measuring the strain.

  Further, as shown in FIG. 10A, the fastening contact portion (the other fastening contact portion in the figure) 10b is not an annular shape, and is provided with a radial cut groove 12b partially. It may be in a disconnected state. This is because the insertion portion 11b is configured without using a through hole, and therefore, deformation is facilitated according to the bias of the fastening force by the fastening means. Accordingly, it is possible to appropriately change the direction in which the fastening force acts, and it is possible to improve the adhesion with the fastening means in the fastening state (especially when the washer is not used). In the configuration in which the fastening contact portions 10a and 10b are both configured separately, both of the fastening contact portions 10a and 10b can have the same configuration. The same applies to the insertion part 21 in the fastening force transmission part 2, and a configuration in which a cut groove is appropriately provided according to the contact state as a whole can be adopted.

  Furthermore, in any form, it is good also as a structure which provides the cylindrical closure wall 10c and obstruct | occludes the whole or only the space | gap part 4. FIG. By installing this closed wall 10c, at least the gap 4 becomes a closed space, and the strain sensors 6a, 6b, 6c, the power source 5 and the like installed therein are not exposed to the outside, and installed ( It is possible to obtain the effect of preventing the entry of dust, pests, and the like from the vicinity of the tightened place.

  The fastening strength detection device 1 as described above detects whether or not the fastening strength is appropriate when using fastening means for joining the materials A and B to be fastened, and also keeps the fastening state for a long time. It can be used to detect a loose state when maintaining That is, in the initial tightening state, when measuring the originally required tightening strength (joining strength at the time of construction), it is determined whether or not the desired strength is given from the state of the strain sensor, and for a long period of time. It is also possible to detect a loose state by detecting a change in the value of the strain sensor during use.

  Furthermore, as shown in FIG. 11, it can also be used for tension measurement when a specific tension material is tensioned. For example, there is a tension measurement of a tendon when manufacturing prestressed concrete. FIG. 11A illustrates a measurement state of a tendon used for prestressed concrete. That is, prestressed concrete has a prestressing method and a poststressing method. In the case of the prestressing method exclusively, a tension material Y is disposed in the longitudinal direction of the mold X, and the tensioning material Y is tensioned in the longitudinal direction. In this state, the concrete Z is placed on the formwork X, and after the cast concrete is solidified, the tension is loosened, thereby applying a compressive force to the entire concrete. This is a process for constructing a concrete structure that can withstand stress in the extension direction by applying a compressive force to concrete in advance.

  Here, it is important that the tension of the tension material Y is applied with a desired tension (tensile force). Usually, the tension force is applied by a jack or the like, and therefore, the tension force according to the capability of the jack or the like. Was set. When such tension (tensile force) is adjusted to be stronger or moderately adjusted, it is not easy to adjust. Therefore, after applying appropriate tension (tensile force) with a jack or the like, tightening while using this embodiment It can be adjusted by means.

  Here, as shown in FIG. 11 (b), a male thread is engraved on a portion of the tension material Y so that a fastening force can be applied by the nut 8. The fastening strength detection device 1 is inserted between the tension material Y and disposed between the mold X and the nut 8 so that the fastening strength by the nut 8 can be measured. The fastening strength detection device 1 may be installed only on one side of the mold X, but if installed on both sides, it is possible to correct the bias of the fastening force.

  The embodiment of the present invention is as described above, but the above embodiment shows an example of the present invention and is not intended to be limited thereto. Therefore, a part of the above-described embodiment may be modified or other elements may be added.

  For example, FIG. 12 shows a modification of the usage pattern of the present invention. When the fastening means is a bolt 7 and a nut 8, a washer is often used. In particular, in a large structure such as a bridge, it may be forced to provide the washer 9 in order to avoid concentrating the fastening force on the head 72 of the bolt 7. However, depending on the structure, a spring washer (spring washer) may be used to maintain the tightened state using the elastic force of the washer 9 (to prevent loosening). Even in this case, as shown in FIG. 12A, if the fastening contact portions 10a and 10b are provided, the entire elastic force of the spring washer 9 is applied to the fastening contact portions 10a and 10b. Therefore, it can be used in the same manner as the above embodiment.

  Further, as shown in FIG. 12B, there may be a method of using the fastening strength detecting device 1 as a washer without using the washer 9. In this case, as shown in the drawing, a configuration in which the fastening contact portions 10a and 10b are provided is preferable. The reason is that the fastening force acting on the head 72 of the bolt 7 or the nut 8 can be distributed over the whole of the fastening force transmission part 2 and the partition part 3.

  Further, in FIG. 3 showing the usage mode of the first embodiment and FIG. 12 showing the modification example, as a general shape when a general bolt and nut are used as fastening means as a shape of the washer, Although an annular washer has been illustrated, the shape of the washer is not limited to an annular shape. That is, the shape of the outer edge may be a quadrangle or a polygon. Even when using a washer that is inevitably determined according to the type of fastening means or that has a special shape for a special application, the fastening strength detecting device described above can be used. Is.

DESCRIPTION OF SYMBOLS 1 Fastening strength detection apparatus 2 Fastening force transmission part 3 Bulkhead part 4 Space | gap part 5 Power supply etc. 6a, 6b, 6c Strain sensor 7 Bolt 8 Nut 9 Washer 10a, 10b Fastening contact part 10c Closure wall 11a, 11b Insertion part ( Through-hole)
12b Cut groove 21 Insertion part (through hole)
22 Wall surface 30a of fastening force transmitting portion Base side end portion 30b of partition wall portion Outer end portion 31 of partition wall surface 51 of partition wall portion Battery (button cell)
52 processing unit (detection unit, transmission unit)
71 Bolt shaft portion 72 Bolt heads A and B Fastening member H1 Thickness H2 in the height direction of the fastening force transmission portion Thickness P and R in the height direction of the partition portion Virtual circle Q Fastening contact portion Width W2 W2a, W2b Width dimension W2-1 of the partition wall Width dimension W2-2 at the base side end of the partition wall Width dimension X at the outer end of the partition wall X Tensile material Z Concrete

Claims (9)

A fastening strength detecting device having an insertion portion for inserting the shaft portion of the fastening means and used in addition to or in place of the washer,
A fastening force transmitting portion that is formed into a cylindrical shape by a wall surface having an appropriate thickness while forming the insertion portion, and that transmits a fastening force by the fastening means;
A plurality of partition walls configured to form a plate-like member having an appropriate thickness extending radially from the wall surface of the fastening force transmitting portion, and capable of transmitting the fastening force together with the fastening force transmitting portion;
A fastening strength detecting device comprising a strain sensor installed on either or both of the wall surface of the fastening force transmitting portion and the surface of the partition wall portion. The partition wall forms a plurality of voids in the middle of the adjacent partition walls,
The fastening force detection device according to claim 1, further comprising a power source that is installed in any one of the gaps and supplies power to the strain sensor.   In any one of the gaps, a detection unit for detecting the output value of the strain sensor and a transmission unit for transmitting the detection value, the detection unit and the transmission unit are connected to the power source, 3. The fastening strength detecting device according to claim 2, wherein the fastening strength detecting device is installed together with the power source while being connected to another power source.   Two fastening contact portions formed in a substantially annular shape so as to simultaneously contact the end surfaces of the fastening force transmitting portion and the partition portion and disposed on both sides in the direction in which the fastening force by the fastening means acts are provided. The fastening strength detection device according to claim 1, further comprising:   The fastening strength detecting device according to claim 4, wherein at least one of the fastening contact portions is formed integrally with the fastening force transmitting portion and the partition wall portion.   The tightening contact portion is replaced with a strain sensor installed on the wall surface of the tightening transmission portion or the surface of the partition wall in a region not subjected to contact by the tightening force transmission portion or the partition wall, or 6. The fastening strength detecting device according to claim 4 or 5, wherein a strain sensor is installed in addition to these.   The fastening strength detecting device according to any one of claims 1 to 6, wherein a closing wall for surrounding the gap is provided between outer end portions of the adjacent partition walls.   When the fastening means is used together with a washer, the outer periphery of the fastening force transmitting portion has a smaller diameter than the outer periphery of the washer, and the outer end of the partition wall portion projects outward from the outer periphery of the washer. The fastening strength detecting device according to any one of claims 1 to 7.   The partition wall includes end surface portions orthogonal to the direction of action on both sides of the direction of application of the fastening force by the fastening means, and the total area of one end surface part and the area of the end surface of the fastening force transmitting part are 9. The fastening strength detecting device according to claim 8, wherein the total sum is larger than the area of one side surface of the washer to be used.

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