Nut end face grinding amount calculation method, nut assembly method, and locking device

Abstract

This invention relates to the field of fastener technology, specifically to a method for calculating the grinding amount of a nut end face, a nut assembly method, and a locking device. The method for calculating the grinding amount of a nut end face includes: acquiring images of the nut and a mating washer, as well as the pitch of the nut; analyzing the images to obtain the angle between the nut's mounting groove and the stop tongue of the stop washer; and determining the grinding amount of the nut end face based on the nut's pitch and the angle. By implementing this invention, the nut can be successfully assembled with the stop washer after only one grinding operation, eliminating the need for operators to judge the grinding amount visually based on their experience. This avoids the need for multiple grinding operations due to inaccurate judgment of the grinding amount, saving installation and adjustment time.

Description

Technical Field

[0001] This invention relates to the field of fastener technology, specifically to a method for calculating the grinding amount of a nut end face, a nut assembly method, and a locking device. Background Technology

[0002] Installing anti-loosening washers at the ends of nuts is a common method for preventing thread loosening. Round nuts typically have mounting grooves on their outer circumference, and locking washers that mate with them have locking tongues. During assembly, after tightening the locking washer and nut into place, the locking tongue is bent to lock into the mounting groove on the outer circumference of the nut, thus strengthening the connection between the locking washer and the nut. However, during assembly, it often happens that after tightening the locking washer and nut, the locking tongue and the mounting groove do not align. Current techniques typically rely on visual inspection to determine the error, then grind the mounting surface of the nut before reinstalling. Since visual inspection is often inaccurate, multiple grinding and reassembly processes are required to complete the installation of the locking washer and nut, which is time-consuming and labor-intensive. Summary of the Invention

[0003] Therefore, the present invention aims to overcome the shortcomings of the prior art in which the grinding allowance of the round nut assembly surface is inaccurate when judged by visual inspection during the installation of the round nut and the locking washer. It provides a method for calculating the grinding allowance of the nut end face, a method for assembling the nut, and a locking device.

[0004] To address the aforementioned problems, this invention provides a method for calculating the grinding amount of a nut end face, comprising: acquiring images of a nut and a locking washer that mates with the nut, and the pitch of the nut; analyzing the images to obtain the included angle between the mounting groove of the nut and the locking tongue of the locking washer; and determining the grinding amount of the nut end face based on the pitch of the nut and the included angle.

[0005] Optionally, the angle between the mounting groove of the nut and the stop tongue of the stop washer is obtained based on the image analysis, including: determining the center line of the mounting groove and the center line of the stop tongue based on the image; and analyzing the angle between the center line of the mounting groove and the center line of the stop tongue.

[0006] Optionally, the grinding amount of the nut end face can be calculated using the following formula: A / 360°=X / B, where A is the pitch of the nut, X is the grinding amount, and B is the included angle.

[0007] The present invention also provides a method for assembling a nut, comprising: sequentially mounting a retaining washer and a nut onto a shaft; taking an assembly photograph of the retaining washer and the nut; analyzing the assembly photograph to obtain the included angle between the retaining tongue on the retaining washer and the assembly groove on the nut; determining the grinding amount of the nut end face based on the pitch of the nut and the included angle; grinding the thickness of the nut according to the grinding amount; mounting the ground nut on the outer periphery of the retaining tongue with one end abutting against the washer body; and folding the retaining tongue extending outside the nut into the assembly groove.

[0008] Optionally, when taking the assembly photo, the photographing device is coaxially arranged with the nut, and the photographing device is located on the side of the stop tongue opposite to the stop washer.

[0009] Optionally, a keyway is provided on the side wall of the shaft; the process of fitting the stop washer onto the shaft includes: fitting the stop washer onto the outer periphery of the shaft, rotating the stop washer until the stop tongue corresponds to the keyway, and bending the stop tongue to fit into the keyway.

[0010] Optionally, the step of sequentially mounting the retaining washer and nut onto the shaft further includes: mounting the nut onto the outer periphery of the retaining tongue, with one end of the nut abutting against the washer body.

[0011] The present invention also provides a locking device applicable to the assembly method of the nut described in any of the above embodiments, comprising: a locking washer having a washer body and a locking tongue disposed on the inner circumference of the washer body, the washer body being adapted to be sleeved on a shaft; a nut being sleeved on the shaft and located outside the locking tongue, one end abutting against the washer body; an assembly groove being provided on the outer circumference of the nut; wherein, one end of the locking tongue located inside the nut is adapted to fit into a keyway on the shaft, and one end of the locking tongue protruding from the nut is folded over to fit into the assembly groove.

[0012] Optionally, the stop tongue has a pair, evenly distributed on the inner circumference of the washer body; the mounting groove has at least one set, each set having a pair of mounting grooves evenly distributed on the outer circumference of the nut.

[0013] Optionally, the included angle is the angle between the centerline of one of the stop tongue pieces and the centerline of the adjacent mounting groove.

[0014] The present invention has the following advantages:

[0015] This invention provides a method for calculating the grinding amount of a nut end face, comprising: acquiring images of a nut and a locking washer that mates with the nut, and the pitch of the nut; obtaining the included angle between the mounting groove of the nut and the locking tongue of the locking washer based on image analysis; and determining the grinding amount of the nut end face based on the pitch of the nut and the included angle.

[0016] This method obtains the grinding amount of the nut by measuring the angle between the mounting groove of the nut in the tightened state and the retaining tongue on the retaining washer. This allows the nut to be successfully assembled with the retaining washer after only one grinding operation, eliminating the need for operators to judge the grinding amount by their own experience and visual inspection. This avoids the need for multiple grinding operations due to inaccurate judgment of the grinding amount, saving installation and adjustment time. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 A flowchart of the method for calculating the grinding amount of the nut end face provided in an embodiment of the present invention is shown.

[0019] Figure 2 A flowchart of a nut assembly method provided in an embodiment of the present invention is shown.

[0020] Figure 3 A front view of the locking washer of the locking device provided in an embodiment of the present invention is shown.

[0021] Figure 4 A cross-sectional view (AA) of the locking washer of the locking device provided in an embodiment of the present invention is shown.

[0022] Figure 5 A front view of the nut of the locking device provided in an embodiment of the present invention is shown.

[0023] Figure 6 A BB cross-sectional view of the nut of the locking device provided in an embodiment of the present invention is shown.

[0024] Figure 7 A schematic diagram showing the included angle between the nut and the retaining tongue provided in an embodiment of the present invention is shown.

[0025] Explanation of reference numerals in the attached figures:

[0026] 1. Nut; 11. Assembly slot; 2. Locking washer; 21. Locking tongue; 22. Washer body. Detailed Implementation

[0027] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0031] This embodiment provides a method for calculating the grinding amount of the nut end face, such as... Figure 1 As shown, the method mainly includes:

[0032] Step S101: Obtain as follows Figure 7 The image shown depicts the nut 1 and the locking washer 2 that mates with the nut 1, and as shown... Figure 6 The pitch of nut 1 is shown. In this embodiment, the image may be obtained by taking a picture using a camera device (e.g., a digital camera, a mobile terminal with a camera function).

[0033] Step S102: Obtain the included angle between the assembly groove 11 of the nut 1 and the stop tongue 21 of the stop washer 2 based on image analysis. Image analysis can be performed using a computer device that is connected to the camera device via communication (e.g., Wi-Fi, LAN, wired, Bluetooth, etc.). Specifically, step S102 includes:

[0034] Step S1021: Determine the center line of the assembly groove 11 and the center line of the stop tongue 21 based on the image. In this embodiment, image recognition can be performed based on the image of the nut 1 and the stop washer 2 that mates with the nut 1 to determine the center line of the assembly groove 11 and the center line of the stop tongue 21. As a specific implementation method, a convolutional neural network can be used for image recognition. First, the obtained image of the mating of the nut 1 and the stop washer 2 is used as the input layer. Then, the input layer is convolved to extract all features in the image to obtain the convolutional layer. Finally, the convolutional layer is downsampled. The assembly groove 11 of nut 1 and the stop tongue 21 of stop washer 2 in the image are extracted as the main target features to obtain a pooling layer. Finally, the pooling layer is classified to obtain a fully connected layer, that is, the center line of assembly groove 11 and the center line of stop tongue 21 are obtained respectively. As another specific implementation method, the boundary features of the obtained mating image of nut 1 and stop washer 2 can be extracted, and the corresponding assembly drawing can be generated in the two-dimensional coordinate system of the modeling software. The expressions of the center line of assembly groove 11 and the center line of stop tongue 21 can be obtained according to the coordinate features of the assembly drawing in the two-dimensional coordinate system. Alternatively, the assembly drawing of nut 1 and stop washer 2 at the same scale can be drawn manually, and the center line of assembly groove 11 and the center line of stop tongue 21 can be determined according to the assembly drawing.

[0035] Step S1022: Analyze and obtain the included angle between the centerline of the assembly groove 11 and the centerline of the stop tongue 21. After determining the centerline of the assembly groove 11 and the centerline of the stop tongue 21, the included angle between the two centerlines can be determined. As a specific implementation method, a protractor tool in a computer can be used to measure the included angle.

[0036] Step S103: Determine the grinding amount of the end face of nut 1 based on the pitch and included angle of nut 1. Specifically, the formula for calculating the grinding amount of the end face of nut 1 is A / 360°=X / B, where A is the pitch of nut 1, X is the grinding amount, and B is the included angle. The grinding surface of nut 1 can be any end face of nut 1, without further limitation. The end face of nut 1 can be ground using a grinding machine. As an alternative implementation, it can also be milled using a milling machine or turned using a lathe.

[0037] The method for calculating the grinding amount of the nut end face in this embodiment obtains the included angle between the assembly groove 11 of the nut 1 in the tightened state and the stop tongue 21 on the stop washer 2, thereby obtaining the grinding amount of the nut 1. This allows the nut 1 to be successfully assembled with the stop washer 2 after only one grinding, eliminating the need for operators to judge the grinding amount by their own experience and visual inspection. This avoids the need for operators to perform multiple grinding operations due to inaccurate judgment of the grinding amount, saving installation and adjustment time.

[0038] This embodiment also provides a method for assembling a nut, such as... Figure 2 As shown, the method mainly includes:

[0039] Step S104: Install the retaining washer 2 and nut 1 onto the shaft in sequence. Specifically, a keyway is provided on the side wall of the shaft. Step S104 includes: Step S1041: Install the retaining washer 2 onto the outer circumference of the shaft, and rotate the retaining washer 2 until the retaining tongue 21 corresponds to the keyway, and bend the retaining tongue 21 until it fits into the keyway; Step S1042: Install the nut 1 onto the outer circumference of the retaining tongue 21, with one end of the nut 1 abutting against the washer body 22, that is, one end of the nut 1 presses against the washer body 22 to achieve a better anti-loosening effect. The shape and size of the keyway are not further limited here, as long as it is suitable for assembling the retaining tongue 21.

[0040] Step S105: Take an assembly photograph of the retaining washer 2 and the nut 1. Furthermore, when taking the assembly photograph, the photographing device is coaxially positioned with the nut 1, and the photographing device is located on the side of the retaining tongue 21 opposite to the retaining washer 2, thereby ensuring that the assembly photograph is proportional to the actual object and avoiding photographic distortion. After step S105, the photographing device uploads the assembly photograph to the image processing device. No further limitations are made on the photographing device and the image processing device here; the photographing device can be a camera, and the image processing device can be a computer, with the computer and camera connected via communication (e.g., Wi-Fi connection, LAN connection, wired connection, Bluetooth connection, etc.).

[0041] Step S106: Analyze the assembly photograph to obtain the included angle between the stop tongue 21 on the stop washer 2 and the assembly groove 11 on the nut 1. As a specific implementation, when analyzing the included angle between the stop tongue 21 and the assembly groove 11, an assembly drawing can be created to scale based on the assembly photograph. The center lines of the stop tongue 21 and the assembly groove 11 can be drawn in the assembly drawing, and the included angle between them can be measured. As another specific implementation, boundary features are extracted from the assembly photograph, and an assembly drawing of the nut 1 and the stop washer 2 is generated in a two-dimensional coordinate system. Based on the coordinate features of the assembly drawing in the two-dimensional coordinate system, expressions for the center lines of the stop tongue 21 and the assembly groove 11 are calculated. The included angle between the center lines of the stop tongue 21 and the assembly groove 11 is then calculated based on these two expressions.

[0042] Step S107: Determine the grinding amount of the end face of nut 1 based on the pitch and included angle of nut 1. Specifically, the formula for calculating the grinding amount of the end face of nut 1 is A / 360°=X / B, where A is the pitch of nut 1, X is the grinding amount, and B is the included angle.

[0043] Step S108: Grind the thickness of nut 1 according to the grinding amount. The grinding method is not further limited here. For example, the end face of nut 1 can be ground by grinding machine. As an alternative implementation, milling machine or lathe can be used for milling.

[0044] Step S109: The ground nut 1 is fitted onto the outer periphery of the stop tongue 21 with one end abutting against the washer body 22. The stop tongue 21, which extends outside the nut 1, is folded into the assembly groove 11, which can be a through groove.

[0045] The nut assembly method provided in this embodiment involves a robotic arm clamping the washer body 22 of the retaining washer 2 and fitting the retaining washer 2 onto the shaft at a set position. The washer body 22 is rotated until the retaining tongue 21 corresponds to the keyway position. The retaining tongue 21 is then bent to fit into the keyway of the shaft. The robotic arm then clamps the nut 1 and fits it onto the outer periphery of the retaining tongue 21, with one end abutting against and pressing the washer body 22. An imaging device takes an assembly photo along the axial direction of the nut 1 and uploads it to a computer. The computer models the assembly photo to obtain the angle between the centerline of the assembly groove 11 and the centerline of the retaining tongue 21. The computer then obtains the grinding amount X from the angle data. The robotic arm moves the nut 1 to a grinding device and grinds the corresponding amount. Finally, the ground nut 1 is reassembled onto the outer periphery of the retaining tongue 21. The robotic arm folds the retaining tongue 21, which extends outside the nut 1, into the assembly groove 11, thus completing the assembly. The robotic arm, computer, and grinding equipment can communicate with each other. The control module on the computer controls the robotic arm and grinding equipment to achieve automated assembly. This assembly method allows for the one-time assembly of nut 1 and retaining washer 2, eliminating the need for multiple experiments and resulting in high assembly efficiency.

[0046] This embodiment also provides a locking device applicable to the nut assembly method described in any of the above embodiments. The locking device includes: a locking washer 2, such as... Figure 3 and Figure 4 As shown, the device has a washer body 22 and a stop tongue 21 disposed on the inner circumference of the washer body 22. The washer body 22 is adapted to be sleeved on the shaft; nut 1, as shown Figure 5 and Figure 6 As shown, the nut 1 is sleeved on the shaft and located outside the retaining tongue 21, with one end abutting against the washer body 22; the outer periphery of the nut 1 is provided with a mounting groove 11, the shape of which is not further limited here, as long as it fits the retaining tongue 21; wherein, the end of the retaining tongue 21 located inside the nut 1 is adapted to fit into the keyway on the shaft, and the end of the retaining tongue 21 protruding from the nut 1 is folded over to fit into the mounting groove 11. Specifically, the nut 1 is a round nut.

[0047] Optionally, a pair of retaining tongues 21 are evenly distributed on the inner circumference of the washer body 22 to strengthen the connection between the retaining washer 2 and the nut 1 and ensure the stability of the connection. The mounting grooves 11 have at least one set, each set having a pair of mounting grooves 11 evenly distributed on the outer circumference of the nut 1. Since a pair of retaining tongues 21 can be matched with different sets of mounting grooves 11, the retaining tongues 21 can be selected to match adjacent mounting grooves 11, thus reducing the grinding amount of the nut 1, avoiding a reduction in the strength of the nut 1, and preventing breakage under stress. The included angle is the angle between the centerline of one retaining tongue 21 and the centerline of the adjacent mounting groove 11. Figure 7 The median angle C is the included angle. As a specific implementation method, such as... Figure 7 As shown, the stop tongue 21 has a pair, and the mounting groove 11 has eight.

[0048] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for calculating the grinding amount of a nut end face, characterized in that, include: Images of the nut (1) and the locking washer (2) that mates with the nut (1), as well as the pitch of the nut (1); Based on the image analysis, the included angle between the assembly groove (11) of the nut (1) and the stop tongue (21) of the stop washer (2) is obtained, including: determining the center line of the assembly groove (11) and the center line of the stop tongue (21) based on the image, and analyzing the included angle between the center line of the assembly groove (11) and the center line of the stop tongue (21). The grinding amount of the end face of the nut (1) is determined based on the pitch of the nut (1) and the included angle, and is calculated using the following formula: A / 360° = X / B Wherein, A is the pitch of the nut (1), X is the grinding amount, and B is the included angle.

2. A method for assembling a nut, characterized in that, include: Install the retaining washer (2) and nut (1) onto the shaft in sequence; Take a photograph of the assembly of the retaining washer (2) and the nut (1); The angle between the stop tongue (21) on the stop washer (2) and the assembly groove (11) on the nut (1) is obtained based on the assembly photos, including: determining the center line of the assembly groove (11) and the center line of the stop tongue (21) based on the images, and analyzing the angle between the center line of the assembly groove (11) and the center line of the stop tongue (21). The grinding amount of the end face of the nut (1) is determined based on the pitch of the nut (1) and the included angle, and is calculated using the following formula: A / 360° = X / B Where A is the pitch of the nut (1), X is the grinding amount, and B is the included angle; The thickness of the nut (1) is ground according to the grinding amount; The ground nut (1) is fitted onto the outer periphery of the stop tongue (21) with one end abutting against the washer body (22), and the stop tongue (21) extending outside the nut (1) is folded into the mounting groove (11).

3. The nut assembly method according to claim 2, characterized in that, When taking the assembly photos, the camera is coaxially positioned with the nut (1) and the camera is located on the side of the stop tongue (21) away from the stop washer (2).

4. The nut assembly method according to claim 2 or 3, characterized in that, The shaft has a keyway on its side wall; The process of fitting the retaining washer (2) onto the shaft includes: The stop washer (2) is fitted onto the outer periphery of the shaft, and the stop washer (2) is rotated until the stop tongue (21) corresponds to the keyway. The stop tongue (21) is then bent to fit into the keyway.

5. The nut assembly method according to claim 4, characterized in that, The step of sequentially mounting the retaining washer (2) and nut (1) onto the shaft also includes: The nut (1) is fitted onto the outer periphery of the stop tongue (21), and one end of the nut (1) abuts against the washer body (22).

6. A locking device, applicable to the assembly method of a nut as described in any one of claims 2-5, characterized in that, include: The stop washer (2) has a washer body (22) and a stop tongue (21) disposed on the inner circumference of the washer body (22), the washer body (22) being adapted to be sleeved on the shaft; The nut (1) is sleeved on the shaft and located outside the stop tongue (21), with one end abutting against the washer body (22); the outer periphery of the nut (1) is provided with an assembly groove (11). The stop tongue (21) is located inside the nut (1) at one end, which is adapted to fit into the keyway on the shaft. The stop tongue (21) protrudes from the nut (1) at one end and is folded to fit into the assembly groove (11).

7. The locking device according to claim 6, characterized in that, The stop tongue (21) has a pair and is evenly distributed on the inner circumference of the washer body (22); the mounting groove (11) has at least one set, each set having a pair of mounting grooves (11) evenly distributed on the outer circumference of the nut (1).

8. The locking device according to claim 7, characterized in that, The included angle is the angle between the center line of one of the stop tongues (21) and the center line of the adjacent assembly groove (11).

Images