Force measuring bolt

Abstract

The utility model provides a force measuring bolt which is applied to the technical field of testing and comprises a bolt body, and a hole communicated with the outside is formed in the bolt body in the axial direction. The strain unit is located in the hole, the strain unit comprises a first strain subunit, a second strain subunit, a third strain subunit and a fourth strain subunit, and the first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are electrically connected to form a full-bridge circuit; and the signal transmission assembly is electrically connected with the full-bridge circuit. The voltage signals measured by the second strain subunit and the fourth strain subunit in the force measuring bolt are mainly related to the influence of temperature, and the temperature influence part in the voltage signals measured by the first strain subunit and the third strain subunit can be counteracted, so that the accuracy of the force measuring result is improved.

Description

Technical Field

[0001] The present application relates to the field of testing technology, and in particular to a force measuring bolt. Background Art

[0002] In order to measure the preload applied during bolt connection, the bolt needs to be modified so that the bolt itself can sense stress or strain. An existing solution for measuring force bolts is to install a 1 / 4 strain gauge in the inner hole of the bolt. When the bolt is strained, the resistance value of the 1 / 4 strain gauge will change, causing the resistance in the bridge to be unbalanced, thereby outputting a voltage signal. By measuring the size of this voltage signal, the size of the strain on the object being measured can be calculated. However, in an environment with large temperature changes, the force measurement results of the 1 / 4 strain gauge will be affected by temperature, resulting in low accuracy of the force measurement results. Utility Model Content

[0003] The embodiment of the present application provides a force measuring bolt to solve the problem of poor force measuring accuracy of existing force measuring bolts.

[0004] In order to solve the above technical problems, this application is implemented as follows:

[0005] In a first aspect, an embodiment of the present application provides a force measuring bolt, the force measuring bolt comprising:

[0006] A bolt body, wherein the bolt body is provided with a hole communicating with the outside along the axial direction;

[0007] A strain unit, the strain unit is located in the hole, the strain unit includes a first strain subunit, a second strain subunit, a third strain subunit and a fourth strain subunit, the first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are electrically connected to form a full-bridge circuit;

[0008] a signal transmission component, the signal transmission component being electrically connected to the full-bridge circuit;

[0009] The first strain subunit and the third strain subunit are used to measure the total strain of the bolt body, and the second strain subunit and the fourth strain subunit are used to measure the strain of the bolt body caused by temperature.

[0010] Optionally, the first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are integrated into a first strain gauge, and the first strain gauge is attached to the hole;

[0011] The long gates of the sensitive gates of the first strain subunit and the long gates of the sensitive gates of the third strain subunit both extend along the axial direction of the bolt body, and the long gates of the sensitive gates of the second strain subunit and the long gates of the sensitive gates of the fourth strain subunit both extend in a direction perpendicular to the axial direction.

[0012] Optionally, the first strain gauge is cylindrical and fits in the hole.

[0013] Optionally, the strain unit further includes four wires fixed to the inner wall of the cylinder of the first strain gauge and extending out of the cylinder, and the strain unit is electrically connected to the signal transmission component through the four wires.

[0014] Optionally, the four wires include a first wire, a second wire, a third wire and a fourth wire, the first strain subunit and the second strain subunit are electrically connected through the first wire, the second strain subunit and the third strain subunit are electrically connected through the second wire, the third strain subunit and the fourth strain subunit are electrically connected through the third wire, and the fourth strain subunit and the first strain subunit are electrically connected through the fourth wire.

[0015] Optionally, the first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are arranged in a matrix on the first strain gauge.

[0016] Optionally, the first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are arranged in a 2×2 matrix on the first strain gauge;

[0017] The first strain subunit and the second strain subunit are located in the first row of the matrix, the third strain subunit and the fourth strain subunit are located in the second row of the matrix, the first strain subunit and the fourth strain subunit are opposite to each other, and the second strain subunit and the fourth strain subunit are opposite to each other.

[0018] Optionally, the first strain subunit and the third strain subunit are integrated into a second strain gauge, the second strain subunit and the fourth strain subunit are integrated into a third strain gauge, the second strain gauge is attached to the hole, and the third strain gauge is placed in the hole;

[0019] The long grid of the sensitive grid of the first strain subunit, the long grid of the sensitive grid of the second strain subunit, the long grid of the sensitive grid of the third strain subunit and the long grid of the sensitive grid of the fourth strain subunit all extend along the axial direction of the bolt body.

[0020] Optionally, the second strain gauge is cylindrical and fits in the hole, and the third strain gauge is cylindrical and placed in the hole.

[0021] Optionally, the strain unit further includes four wires fixed to the inner wall of the cylinder of the second strain gauge and the inner wall of the cylinder of the third strain gauge and extending out of the cylinder, and the strain unit is electrically connected to the signal transmission component through the four wires.

[0022] Optionally, the four wires include a fifth wire, a sixth wire, a seventh wire and an eighth wire, the first pin of the first strain subunit and the first pin of the fourth strain subunit are electrically connected through the fifth wire, the second pin of the first strain subunit and the first pin of the second strain subunit are electrically connected through the sixth wire, the first pin of the third strain subunit and the second pin of the fourth strain subunit are electrically connected through the seventh wire, and the second pin of the third strain subunit and the second pin of the second strain subunit are electrically connected through the eighth wire.

[0023] Optionally, the bolt body includes a screw rod and a bolt head, the screw rod is axially provided with a hole communicating with the outside, the bolt head is provided with a recess, and the signal transmission component is fixed in the recess.

[0024] Optionally, the signal transmission component is a digital amplifier circuit component, which includes a digital amplifier circuit, and the digital amplifier circuit is used to amplify the output voltage signal of the full-bridge circuit into a digital signal and transmit the digital signal to a signal processor.

[0025] Optionally, the signal transmission component is a connector, and the connector is used to transmit the voltage signal output by the full-bridge circuit to a digital meter or a strain gauge.

[0026] Optionally, the diameter of the hole is greater than 1 mm and less than or equal to 3 mm.

[0027] The force measuring bolt of the embodiment of the present application comprises a bolt body, wherein the bolt body is provided with a hole connected to the outside along the axial direction; a strain unit, wherein the strain unit is located in the hole, wherein the strain unit comprises a first strain subunit, a second strain subunit, a third strain subunit and a fourth strain subunit, wherein the first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are electrically connected to form a full-bridge circuit; and a signal transmission component, wherein the signal transmission component is electrically connected to the full-bridge circuit; wherein the first strain subunit and the third strain subunit are used to measure the total strain of the bolt body, and the second strain subunit and the fourth strain subunit are used to measure the strain of the bolt body caused by temperature. In the force measuring bolt, the voltage signals measured by the first strain subunit and the third strain subunit are related to the influence of temperature and force, and the voltage signals measured by the second strain subunit and the fourth strain subunit are mainly related to the influence of temperature, which can offset the temperature-affected part of the voltage signals measured by the first strain subunit and the third strain subunit, thereby making the voltage signal output by the full-bridge circuit only related to the influence of force, thereby improving the accuracy of the force measurement result obtained by the force measuring bolt according to the voltage signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0029] Figure 1 It is one of the schematic diagrams of the force measuring bolt provided in the embodiment of the present application;

[0030] Figure 2 is a schematic diagram of a full-bridge circuit provided in an embodiment of the present application;

[0031] Figure 3 is a schematic diagram of the expansion of the first strain gauge provided in an embodiment of the present application;

[0032] Figure 4 is a schematic diagram of the formation of the first strain gauge provided in an embodiment of the present application;

[0033] Figure 5 is a schematic diagram of the appearance of a first strain gauge provided in an embodiment of the present application;

[0034] Figure 6 This is the second schematic diagram of the force measuring bolt provided in the embodiment of the present application;

[0035] Figure 7 is a schematic diagram of the expansion of the second strain gauge and the third strain gauge provided in the embodiment of the present application;

[0036] Figure 8 This is the third schematic diagram of the force measuring bolt provided in the embodiment of the present application. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0038] The present application embodiment provides a force measuring bolt. Figure 1 , Figure 1 Schematic diagram of a force measuring bolt provided in an embodiment of the present application, such as Figure 1 As shown, the force measuring bolt comprises:

[0039] A bolt body 1, wherein the bolt body 1 is provided with a hole 2 communicating with the outside along the axial direction;

[0040] A strain unit 3, the strain unit 3 is located in the hole 2, the strain unit 3 comprises a first strain subunit 31, a second strain subunit 32, a third strain subunit 33 and a fourth strain subunit 34, the first strain subunit 31, the second strain subunit 32, the third strain subunit 33 and the fourth strain subunit 34 are electrically connected to form a full-bridge circuit;

[0041] A signal transmission component 4, wherein the signal transmission component 4 is electrically connected to the full-bridge circuit;

[0042] The first strain subunit 31 and the third strain subunit 33 are used to measure the total strain of the bolt body, and the second strain subunit 32 and the fourth strain subunit 34 are used to measure the strain of the bolt body 1 caused by temperature.

[0043] In one embodiment, see Figure 2 , Figure 2 It is a full bridge circuit composed of a first strain subunit 31 (resistance value corresponds to R1 in the figure), a second strain subunit 32 (resistance value corresponds to R2 in the figure), a third strain subunit 33 (resistance value corresponds to R3 in the figure) and a fourth strain subunit 34 (resistance value corresponds to R4 in the figure). The corner points 2 and 3 of the bridge are the bridge excitation voltage Vs; the corner points 1 and 4 are the bridge output voltage Vo, that is, the output voltage signal.

[0044] According to the relevant principles of the Wheatstone bridge, the following equation can be obtained:

[0045]

[0046] If R2 and R4 are used as the resistors of the compensation sheet, then R2 and R4 are not subjected to force, and △R2 and △R4 are the changes caused by temperature. If R1 and R3 are used as the resistors of the working sheet, their resistance changes are affected by temperature and force. It can be assumed that the initial resistance of the four resistors is the same. Since the initial resistance is the same, the results of thermal influence are also the same. It can be seen from the above equation that the compensation sheet is placed in positions 2 and 4, and is not subjected to external force or the influence of external force can be ignored. Its resistance change is mainly affected by temperature. Connecting to the bridge circuit can offset the influence of the working sheet on the force measurement result due to temperature change, thereby realizing temperature compensation on the bridge circuit.

[0047] The voltage signal output by the full-bridge circuit is transmitted by the signal transmission component 4. The signal transmission component 4 can be a digital circuit amplifier component. The digital circuit amplifier component has a digital amplifier circuit. The digital amplifier circuit can amplify the voltage signal into a digital signal. The digital circuit amplifier component can transmit the digital signal to the signal processor for processing via a connected data line to obtain the force measurement result of the bolt body. The signal transmission component 4 can also be a connector. The connector can transmit the voltage signal to a digital instrument or a strain gauge for processing to obtain the force measurement result of the bolt body.

[0048] In this embodiment, the voltage signals measured by the first strain subunit 31 and the third strain subunit 33 are related to the influence of temperature and force, and the voltage signals measured by the second strain subunit 32 and the fourth strain subunit 34 are mainly related to the influence of temperature, which can offset the temperature-affected portion of the voltage signals measured by the first strain subunit 31 and the third strain subunit 33, so that the voltage signal output by the full-bridge circuit is only related to the influence of force, thereby improving the accuracy of the subsequent force measurement results obtained by the force measuring bolt based on the voltage signal.

[0049] Optionally, the first strain subunit 31, the second strain subunit 32, the third strain subunit 33 and the fourth strain subunit 34 are integrated into a first strain gauge 5, and the first strain gauge 5 is attached to the hole 2;

[0050] The long gates of the sensitive gates of the first strain subunit 31 and the long gates of the sensitive gates of the third strain subunit 33 both extend along the axial direction of the bolt body 1, and the long gates of the sensitive gates of the second strain subunit 32 and the long gates of the sensitive gates of the fourth strain subunit 34 both extend in a direction perpendicular to the axial direction.

[0051] In one embodiment, see Figure 3 , Figure 3: is a schematic diagram of the expansion of the first strain gauge 5. In the first strain gauge 5, the long grid of the sensitive grid of the first strain subunit 31 and the long grid of the sensitive grid of the third strain subunit 33 both extend along the axial direction of the bolt body 1. Since the bolt body 1 is mainly subjected to axial force, the sensitive grid of the first strain subunit 31 and the sensitive grid of the third strain subunit 33 will be deformed due to the axial force of the bolt body 1 and the change of the external temperature, so that the resistance values ​​of the first strain subunit 31 and the third strain subunit 33 change; and the long grid of the sensitive grid of the second strain subunit 32 and the long grid of the sensitive grid of the fourth strain subunit 34 both extend in a direction perpendicular to the axial direction, so the sensitive grids of the second strain subunit 32 and the fourth strain subunit 34 will hardly sense the axial force, and the sensitive grids of the second strain subunit 31 and the fourth strain subunit 33 will only be deformed due to the change of the external temperature, so that the resistance values ​​of the first strain subunit 31 and the third strain subunit 33 change.

[0052] In this embodiment, through the setting of different sensitive gates, the voltage signals measured by the first strain subunit and the third strain subunit are related to the influence of temperature and force, and the voltage signals measured by the second strain subunit and the fourth strain subunit are almost not affected by external force and are mainly related to the influence of temperature. The temperature-affected part of the voltage signals measured by the first strain subunit and the third strain subunit can be offset, so that the voltage signal output by the full-bridge circuit is only related to the influence of force, thereby improving the accuracy of the subsequent force measurement results obtained by the force measuring bolt based on the voltage signal.

[0053] Optionally, the first strain gauge 5 is cylindrical and fits inside the hole 2 .

[0054] In one embodiment, see Figure 4 and Figure 5 , Figure 3 The first strain gauge 5 in the embodiment is rolled into a cylindrical shape from an unfolded state and then attached to the hole 2. Alternatively, the first strain gauge 5 can be integrally formed into a cylindrical shape and then attached to the hole 2. The attached state can be seen in FIG. Figure 6 .

[0055] There are two bonding methods: one is to use special glue to stick the outer surface of the cylindrical first strain gauge 5 to the inner surface of the hole; the other is to fill the inner surface of the cylindrical first strain gauge 5 with special glue so that the outer surface of the first strain gauge 5 is attached to the inner surface of the hole.

[0056] In addition to the embodiments mentioned in this application, the first strain gauge 5 may also be in other geometric shapes, such as a cube. In the embodiments of this application, the first strain gauge 5 is cylindrically fitted in the hole 2, which can improve the fit between the first strain gauge 5 and the hole 2, thereby improving the accuracy of the first strain gauge 5 sensing the strain of the bolt body 1.

[0057] Optionally, the strain unit 3 further includes four wires fixed to the inner wall of the cylinder of the first strain gauge 5 and extending out of the cylinder, and the strain unit 3 is electrically connected to the signal transmission component 4 through the four wires.

[0058] In one embodiment, continue to refer to Figure 3 Optionally, the four wires include a first wire 61, a second wire 62, a third wire 63 and a fourth wire 64, the first strain subunit 31 and the second strain subunit 32 are electrically connected through the first wire 61, the second strain subunit 32 and the third strain subunit 33 are electrically connected through the second wire 62, the third strain subunit 33 and the fourth strain subunit 34 are electrically connected through the third wire 63, and the fourth strain subunit 34 and the first strain subunit 31 are electrically connected through the fourth wire 64, so that the strain unit can effectively transmit the voltage signal to the signal transmission component.

[0059] Optionally, the first strain subunit 31 , the second strain subunit 32 , the third strain subunit 33 and the fourth strain subunit 34 are arranged in a matrix on the first strain gauge 5 .

[0060] In one embodiment, continue to refer to Figure 3 When the first strain gauge 5 is unfolded, the strain sub-units are arranged in a matrix manner on the first strain gauge 5 in accordance with the positional arrangement of the strain sub-units in the full-bridge circuit. Combined with the working principle of the full-bridge circuit, it is beneficial to subsequently obtain accurate voltage signals according to the resistance changes of the strain sub-units, thereby improving the accuracy of the force measurement results.

[0061] Optionally, the first strain subunit 31, the second strain subunit 32, the third strain subunit 33 and the fourth strain subunit 34 are arranged in a 2×2 matrix on the first strain gauge 5;

[0062] The first strain subunit 31 and the second strain subunit 32 are located in the first row of the matrix, the third strain subunit 33 and the fourth strain subunit 34 are located in the second row of the matrix, the first strain subunit 31 and the fourth strain subunit 34 are opposite to each other, and the second strain subunit 32 and the fourth strain subunit 34 are opposite to each other.

[0063] In one embodiment, continue to refer to Figure 3When the first strain gauge 5 is unfolded, the first strain subunit 31 and the second strain subunit 32 are located in the first row of the matrix, the third strain subunit 33 and the fourth strain subunit 34 are located in the second row of the matrix, the first strain subunit 31 and the fourth strain subunit 34 are opposite to each other, and the second strain subunit 32 and the fourth strain subunit 34 are opposite to each other. This arrangement is consistent with the position arrangement of each strain subunit in the full-bridge circuit, combined with the working principle of the full-bridge circuit, so as to facilitate the subsequent acquisition of accurate voltage signals according to the resistance changes of each strain subunit, thereby improving the accuracy of the force measurement results.

[0064] Optionally, the first strain subunit 31 and the third strain subunit 33 are integrated into a second strain gauge 7, the second strain subunit 32 and the fourth strain subunit 34 are integrated into a third strain gauge 8, the second strain gauge 7 is attached to the hole, and the third strain gauge 8 is placed in the hole;

[0065] The long grids of the sensitive grids of the first strain subunit 31 , the second strain subunit 32 , the third strain subunit 33 and the fourth strain subunit 34 all extend along the axial direction of the bolt body 1 .

[0066] In one embodiment, see Figure 7 The first strain subunit 31 and the third strain subunit 33 are integrated into a second strain gauge 7, which is attached to the hole. The long grid of the sensitive grid of the first strain subunit 31 and the long grid of the sensitive grid of the third strain subunit 33 extend along the axial direction of the bolt body 1. Therefore, the sensitive grid of the first strain subunit 31 and the sensitive grid of the third strain subunit 33 will be deformed due to the axial force of the bolt body 1 and the change of the external temperature, so that the resistance values ​​of the first strain subunit 31 and the third strain subunit 33 change; the second strain subunit 32 and the fourth strain subunit 34 are integrated into a third strain gauge 8, which is freely placed in the hole. Since the third strain gauge 8 is not attached to the hole, the sensitive grids of the second strain subunit 32 and the fourth strain subunit 34 will not be affected by external forces, and the sensitive grids of the second strain subunit 31 and the fourth strain subunit 33 will only be deformed due to the change of the external temperature, so that the resistance values ​​of the first strain subunit 31 and the third strain subunit 33 change.

[0067] In this embodiment, through the different placement states of the strain gauge in the hole, the voltage signals measured by the first strain subunit and the third strain subunit are related to the influence of temperature and force, and the voltage signals measured by the second strain subunit and the fourth strain subunit are mainly related to the influence of temperature, which can offset the part of the voltage signal measured by the first strain subunit and the third strain subunit that is affected by temperature, so that the voltage signal output by the full-bridge circuit is only related to the influence of force, thereby improving the accuracy of the subsequent force measurement results obtained by the force measuring bolt based on the voltage signal.

[0068] Optionally, the second strain gauge 7 is cylindrical and fits in the hole 2 , and the third strain gauge 8 is cylindrical and placed in the hole 2 .

[0069] In one embodiment, see Figure 8 , Figure 7 The second strain gauge 7 in the apparatus is rolled into a cylindrical shape from an unfolded state and then attached to the hole 2. There are two ways of attaching: one is to use special glue to make the outer surface of the first strain gauge of the cylinder adhere to the inner surface of the hole; the other is to use special glue to fill the inner surface of the first strain gauge of the cylinder so that the outer surface of the first strain gauge is attached to the inner surface of the hole. The third strain gauge 8 is rolled into a cylindrical shape from an unfolded state and is freely placed in the hole 2.

[0070] In addition to the embodiments mentioned in this application, the second strain gauge 7 may also be in other geometric shapes, such as a cube. In this embodiment, the second strain gauge 7 is fitted into the hole 2 in a cylindrical shape, which can improve the fit between the second strain gauge 7 and the hole 2, thereby improving the accuracy of the second strain gauge 7 in sensing the strain of the bolt body 1. The third strain gauge 8 is rolled into a cylindrical shape to reduce the difficulty of placing the third strain gauge 8 into the hole.

[0071] Optionally, the strain unit 3 further includes four wires fixed to the inner wall of the cylinder of the second strain gauge 7 and the inner wall of the cylinder of the third strain gauge 8 and extending out of the cylinder, and the strain unit 3 is electrically connected to the signal transmission component 4 through the four wires.

[0072] In one embodiment, continue to refer to Figure 7Optionally, the four wires may include a fifth wire 65, a sixth wire 66, a seventh wire 67 and an eighth wire 68, the first pin 311 of the first strain subunit 31 and the first pin 341 of the fourth strain subunit 34 are electrically connected through the fifth wire 65, the second pin 312 of the first strain subunit 31 and the first pin 321 of the second strain subunit 32 are electrically connected through the sixth wire 66, the first pin 331 of the third strain subunit 33 and the second pin 342 of the fourth strain subunit 34 are electrically connected through the seventh wire 67, and the second pin 332 of the third strain subunit 33 and the second pin 322 of the second strain subunit 32 are electrically connected through the eighth wire 68, so that the voltage signal output by the full-bridge circuit is effectively transmitted to the signal transmission component through the wires.

[0073] Optionally, the bolt body 1 includes a screw rod 11 and a bolt head 12 , the screw rod 11 is axially provided with a hole 2 communicating with the outside, the bolt head 12 is provided with a recess 121 , and the signal transmission component 4 is fixed in the recess 121 .

[0074] In one embodiment, continue to refer to Figure 1 A hole 2 connected to the outside is set axially on the screw rod 11 to avoid damage to the bolt body. In this way, axial force information can be obtained without damaging the bolt body, which helps to extend the service life of the bolt body; by opening a recess 121 on the bolt head 12 and fixing the signal transmission component 4 in the recess 121, it is beneficial to improve the stability of the placement of the signal transmission component.

[0075] In addition, it should be noted that the mechanical parts applying the strain unit mentioned in the present application may not be limited to the bolt body, but may also include other mechanical parts such as studs. The technical effects achieved are the same as those of the aforementioned embodiments and will not be repeated here.

[0076] Optionally, the signal transmission component is a digital amplifier circuit component, which includes a digital amplifier circuit, and the digital amplifier circuit is used to amplify the output voltage signal of the full-bridge circuit into a digital signal and transmit the digital signal to a signal processor.

[0077] In this embodiment, the digital circuit amplification component can transmit the digital signal to the signal processor for processing via the connected data line to obtain the force measurement result of the bolt body.

[0078] Optionally, the signal transmission component is a connector, and the connector is used to transmit the voltage signal output by the full-bridge circuit to a digital meter or a strain gauge.

[0079] In this embodiment, the connector can transmit the voltage signal to a digital meter or a strain gauge for processing to obtain the force measurement result of the bolt body.

[0080] Optionally, the diameter of the hole 2 is greater than 1 mm and less than or equal to 3 mm.

[0081] In one embodiment, the diameter of the hole 2 is greater than 1 mm and less than or equal to 3 mm, which is beneficial to save space and provide a more accurate axial full-bridge test for the bolt body.

[0082] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0083] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A force measuring bolt, characterized in that: include: A bolt body, wherein the bolt body is provided with a hole communicating with the outside along the axial direction; A strain unit, the strain unit is located in the hole, the strain unit includes a first strain subunit, a second strain subunit, a third strain subunit and a fourth strain subunit, the first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are electrically connected to form a full-bridge circuit; a signal transmission component, the signal transmission component being electrically connected to the full-bridge circuit; The first strain subunit and the third strain subunit are used to measure the total strain of the bolt body, and the second strain subunit and the fourth strain subunit are used to measure the strain of the bolt body caused by temperature.

2. The force measuring bolt according to claim 1, characterized in that: The first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are integrated into a first strain gauge, and the first strain gauge is attached to the hole; The long gates of the sensitive gates of the first strain subunit and the long gates of the sensitive gates of the third strain subunit both extend along the axial direction of the bolt body, and the long gates of the sensitive gates of the second strain subunit and the long gates of the sensitive gates of the fourth strain subunit both extend in a direction perpendicular to the axial direction.

3. The force measuring bolt according to claim 2, characterized in that: The first strain gauge is cylindrical and fits in the hole.

4. The force measuring bolt according to claim 3, characterized in that: The strain unit also includes four wires fixed to the inner wall of the cylinder of the first strain gauge and extending out of the cylinder. The strain unit is electrically connected to the signal transmission component through the four wires.

5. The force measuring bolt according to claim 4, characterized in that: The four wires include a first wire, a second wire, a third wire and a fourth wire, the first strain subunit and the second strain subunit are electrically connected through the first wire, the second strain subunit and the third strain subunit are electrically connected through the second wire, the third strain subunit and the fourth strain subunit are electrically connected through the third wire, and the fourth strain subunit and the first strain subunit are electrically connected through the fourth wire.

6. The force measuring bolt according to claim 2, characterized in that: The first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are arranged in a matrix on the first strain gauge.

7. The force measuring bolt according to claim 6, characterized in that: The first strain subunit, the second strain subunit, the third strain subunit and the fourth strain subunit are arranged in a 2×2 matrix on the first strain gauge; The first strain subunit and the second strain subunit are located in the first row of the matrix, the third strain subunit and the fourth strain subunit are located in the second row of the matrix, the first strain subunit and the fourth strain subunit are opposite to each other, and the second strain subunit and the fourth strain subunit are opposite to each other.

8. The force measuring bolt according to claim 1, characterized in that: The first strain subunit and the third strain subunit are integrated into a second strain gauge, the second strain subunit and the fourth strain subunit are integrated into a third strain gauge, the second strain gauge is attached to the hole, and the third strain gauge is placed in the hole; The long grid of the sensitive grid of the first strain subunit, the long grid of the sensitive grid of the second strain subunit, the long grid of the sensitive grid of the third strain subunit and the long grid of the sensitive grid of the fourth strain subunit all extend along the axial direction of the bolt body.

9. The force measuring bolt according to claim 8, characterized in that: The second strain gauge is cylindrical and fits in the hole, and the third strain gauge is cylindrical and placed in the hole.

10. The force measuring bolt according to claim 9, characterized in that: The strain unit also includes four wires fixed to the inner wall of the cylinder of the second strain gauge and the inner wall of the cylinder of the third strain gauge and extending out of the cylinder. The strain unit is electrically connected to the signal transmission component through the four wires.

11. The force measuring bolt according to claim 10, characterized in that: The four wires include a fifth wire, a sixth wire, a seventh wire and an eighth wire, the first pin of the first strain subunit and the first pin of the fourth strain subunit are electrically connected through the fifth wire, the second pin of the first strain subunit and the first pin of the second strain subunit are electrically connected through the sixth wire, the first pin of the third strain subunit and the second pin of the fourth strain subunit are electrically connected through the seventh wire, and the second pin of the third strain subunit and the second pin of the second strain subunit are electrically connected through the eighth wire.

12. The force measuring bolt according to claim 1, characterized in that: The bolt body comprises a screw rod and a bolt head. The screw rod is provided with a hole communicating with the outside along the axial direction. The bolt head is provided with a concave platform. The signal transmission component is fixed in the concave platform.

13. The force measuring bolt according to claim 1, characterized in that: The signal transmission component is a digital amplifier circuit component, which includes a digital amplifier circuit. The digital amplifier circuit is used to amplify the output voltage signal of the full-bridge circuit into a digital signal and transmit the digital signal to a signal processor.

14. The force measuring bolt according to claim 1, characterized in that: The signal transmission component is a connector, and the connector is used to transmit the voltage signal output by the full-bridge circuit to a digital instrument or a strain gauge.

15. The force measuring bolt according to any one of claims 1 to 14, characterized in that: The diameter of the hole is greater than 1 mm and less than or equal to 3 mm.

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