Wrench slots, fasteners and fastening tools

Abstract

The present application provides a wrench groove, a fastener, and a fastening tool, which relate to the technical field related to fasteners and are used to solve the problems of the existing wrench grooves being difficult to manufacture, having high processing costs, and thread damage occurring during the processing of the wrench grooves, which leads to fatigue of the fasteners and a decrease in mechanical properties. The wrench groove provided in the present application includes a plurality of connected protrusions, which are arranged at equal angles around the center line of the wrench groove on the inner side wall of the wrench groove; the protrusions protrude radially outward from the wrench groove; and on the cross section of the inner side wall, the protrusions include a first convex arc segment and a second convex arc segment connected to each other. The present application is used for connecting lightweight fastening structures in the aerospace field.

Description

Technical Field

[0001] The present application relates to the technical field related to fasteners, and in particular to a wrench slot, a fastener and a fastening tool. Background Art

[0002] Mechanical structures are usually connected using bolts, nuts, threaded connections, riveted connections, or welded connections, while composite structures can only be connected using bolts and nuts. However, conventional bolt and nut connections cannot control the installation torque and the clamping force of the threaded connection pair on the connected structure.

[0003] In recent years, with the increasing requirements for installation torque, especially in the aerospace field, when fasteners are installed, the wrench groove of the fastener often "slips" during the tightening process. That is, before the fastener reaches the installation torque, the wrench groove on the fastener has already deformed and cannot meet the installation requirements of the fastener. Fastener failures often occur at the installation site, which not only affects the installation efficiency of the fasteners, but also affects the fastening effect of the fasteners.

[0004] In order to solve the above problems, the Chinese patent document with the publication number CN102536990B discloses a fixing component, a male unit, and a handle tool and a measuring meter comprising such a male unit, wherein the groove 01 in the fixing component comprises a peripheral edge in the form of a multi-petal continuous curve, and the cross section of each petal is defined by a series of three continuous arc segments, namely a first convex arc segment 02 with a first radius, a second concave arc segment 03 with a second radius on each side of the first convex arc segment 02, and each petal is connected to the adjacent petal via a third convex arc segment 04 with a third radius larger than the first radius, such as Figure 1 shown.

[0005] However, in the prior art, the protruding portion of each lobe of the groove 01 is defined by a first convex arc segment 02, and the first convex arc segment 02 is connected to the adjacent lobe via a third convex arc segment 04 having a third radius greater than the first radius. In this case, the processing accuracy requirements for each lobe in the above-mentioned groove 01 are relatively high. After processing one lobe and then processing another lobe, it is necessary to ensure the rotation angle of the processing tool, or, if six lobes are processed at the same time, it is necessary to ensure the positional accuracy between the six lobes in the punch, which leads to the difficulty in manufacturing the above-mentioned groove 01 and high processing cost. In addition, thread damage is likely to occur during the processing of the above-mentioned groove 01, and such damage is harmful to the connection of the fastener, and is likely to cause a decline in the fatigue performance and mechanical properties of the fastener in the later stage. Summary of the Invention

[0006] The wrench groove, fastener and fastening tool provided in this application can solve the problems of the existing wrench groove (i.e., groove 01 in the prior art) being difficult to manufacture and having high processing costs, as well as thread damage occurring during the processing of the wrench groove, leading to fatigue of the fastener and a decrease in mechanical properties.

[0007] To achieve the above-mentioned purpose, in the first aspect, the wrench groove provided by the present application includes a plurality of connected protrusions, and the plurality of protrusions are arranged at equal angles around the center line of the wrench groove on the inner side wall of the wrench groove; the protrusions protrude toward the radial outside of the wrench groove; on the cross section of the inner side wall, the protrusions include a first convex arc segment and a second convex arc segment connected.

[0008] In some embodiments of the present application, the first convex arc segment and the second convex arc segment correspond to different centers of circles, and the radius of the first convex arc segment is not equal to the radius of the second convex arc segment.

[0009] In some embodiments of the present application, on the cross-section of the inner wall, the protrusion also includes an outward convex arc transition section, which connects the first convex arc section and the second convex arc section, and the radius of the outward convex arc transition section is much smaller than the radius of the first convex arc section, or much smaller than the radius of the second convex arc section.

[0010] In some embodiments of the present application, when the radius of the first convex arc segment is greater than the radius of the second convex arc segment, the ratio of the radius of the second convex arc segment to the radius of the outer convex arc transition section is: (40~80):1; when the radius of the first convex arc segment is smaller than the radius of the second convex arc segment, the ratio of the radius of the first convex arc segment to the radius of the outer convex arc transition section is: (40~80):1.

[0011] In some embodiments of the present application, there are also multiple concave arc transition sections on the cross-section of the inner side wall, which are used to connect adjacent protrusions; the first convex arc section of each protrusion is connected to the second convex arc section of the adjacent protrusion through the concave arc transition section; the second convex arc section of each protrusion is connected to the first convex arc section of the adjacent protrusion through the concave arc transition section.

[0012] In some embodiments of the present application, the circumscribed circle diameter D1 of the wrench groove and the inscribed circle diameter D2 of the wrench groove satisfy the following: D2 = (0.7-0.95) × D1.

[0013] In some embodiments of the present application, the angle α between the tangent line of the first convex arc segment and the tangent line of the second convex arc segment is 90° to 150°.

[0014] In some embodiments of the present application, the protrusions have the same shape and size in the extension direction of the center line of the wrench groove.

[0015] In a second aspect, the present application further provides a fastener comprising a head and a stem, wherein the above-mentioned wrench groove is provided on the end surface of the head facing away from the stem or on the end surface of the stem facing away from the head.

[0016] In some embodiments of the present application, when the wrench groove is provided on the end surface of the head portion facing away from the rod portion, the radius R1 of the first convex arc segment and the radius R2 of the second convex arc segment satisfy: R1 = (1.1-2) × R2.

[0017] In some embodiments of the present application, when the wrench groove is provided on the end surface of the head portion facing away from the rod portion and the number of the protrusions is an even number, the distance L between two symmetrically arranged protrusions satisfies: L=R1 / (0.5~1).

[0018] In some embodiments of the present application, when the wrench groove is provided on the end surface of the rod portion facing away from the head portion, the radius R1 of the first convex arc segment and the radius R2 of the second convex arc segment satisfy: R2 = (1.1-1.5) × R1.

[0019] In some embodiments of the present application, when the wrench groove is provided on the end surface of the rod portion facing away from the head portion, and the number of the protrusions is an even number, the distance L between two symmetrically arranged protrusions satisfies: L=R1 / (1~1.5).

[0020] In some embodiments of the present application, the rod is provided with a threaded section.

[0021] In some embodiments of the present application, the fastener is a bolt or a countersunk screw.

[0022] On the third aspect, the present application also provides a fastening tool including a fitting portion, which is used to cooperate with the wrench groove in the above-mentioned fastener. The shape of the fitting portion is configured relative to the shape of the wrench groove. When the fitting portion and the wrench groove are fitted with each other and the fastening tool rotates around the center line of the wrench groove, the fitting portion transmits the fastening torque to the fastener through the protrusion of the wrench groove.

[0023] Compared with the prior art, the multiple protrusions in the wrench groove provided by the present application are continuous, and a recessed portion is naturally formed between each adjacent two protrusions, so that the protrusions in the above-mentioned wrench groove can transmit greater torque. At the same time, the multiple protrusions of the present application are continuous, that is, the arc length of the inscribed circle of the wrench groove corresponding to each protrusion is longer, that is, the angle formed by the tangent of the first convex arc segment and the tangent of the second convex arc segment in each protrusion is relatively large, and the waste chips generated in the process of punching the wrench groove are easily discharged. Therefore, the manufacturing difficulty and processing cost of the above-mentioned wrench groove are reduced through the above-mentioned arrangement, and because the punching margin of the wrench groove in the present application is small, when the above-mentioned wrench groove is processed on the fastener, the impact force on the fastener is smaller, that is, the vibration of the fastener is smaller, thereby reducing the risk of thread damage to the fastener during the processing of the above-mentioned wrench groove, thereby improving the fatigue performance and mechanical properties of the fastener.

[0024] Similarly, since the fastener of the present application includes a head and a rod with a threaded section, the wrench groove provided on the end surface of the head away from the rod or the end surface of the rod away from the head and the above-mentioned wrench groove adopt the same structure, so the two can solve the same technical problem and achieve the same expected effect.

[0025] In addition, since the fastening tool of the present application includes an engaging portion that cooperates with the wrench groove in the above-mentioned fastener, the engaging portion transmits the tightening torque to the fastener through the protrusion of the wrench groove, and the engaging portion adopts the same structure as the above-mentioned wrench groove, the two can solve the same technical problem and achieve the same expected effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 It is a schematic structural diagram of a groove in a fixing member in the prior art;

[0028] Figure 2 This is a structural diagram of the wrench groove in the embodiment of the present application;

[0029] Figure 3 This is a structural detail diagram of the wrench groove in the embodiment of the present application, to clearly show the relevant dimensions of the wrench groove;

[0030] Figure 4 1 is a schematic structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a bolt, and a wrench groove is provided on the bolt head;

[0031] Figure 5 yes Figure 4 Left view of;

[0032] Figure 6 1 is a schematic structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a countersunk screw, and a wrench groove is provided on the head of the countersunk screw;

[0033] Figure 7 yes Figure 6 Left view of;

[0034] Figure 8 1 is a schematic structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a bolt and the wrench groove is provided on the bolt shank;

[0035] Figure 9 yes Figure 8 Left view of;

[0036] Figure 10 1 is a schematic structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a countersunk screw, and a wrench groove is provided on the shank of the countersunk screw;

[0037] Figure 11 yes Figure 10 Left view of .

[0038] The main reference numerals in the drawings of this application specification are described as follows:

[0039] 10 (10') - wrench groove; 11 - first convex arc segment; 12 - second convex arc segment; 13 - outer convex arc transition segment; 14 - inner concave arc transition segment; 20 - bolt; 21 - bolt head; 22 - bolt shank; 30 - countersunk screw; 31 - countersunk screw head; 32 - countersunk screw shank. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0041] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0042] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout this application, unless otherwise specified, "plurality" means two or more.

[0043] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0044] Composite materials are increasingly used in aircraft. For example, the C919, a large passenger aircraft currently under development in China, uses over 10% composite materials. Consequently, many tools used with these materials are no longer usable, including traditional high-lock bolts. Traditional high-lock bolts are primarily used to connect metals, employing an interference fit. However, composite materials are less resistant to compression and impact, requiring a clearance fit. Consequently, the torque wrench groove at the tail of traditional high-lock bolts cannot provide the torque required to tighten the nut. Therefore, a new high-lock bolt and supporting tool were developed to enhance the torsion resistance of the wrench groove at the head or shank.

[0045] This application provides a wrench slot 10, a fastener having the wrench slot 10, and a fastening tool for fastening a fastener having the wrench slot 10, each of which is described in detail below. It should be noted that the order in which the following embodiments are described does not limit the preferred order of the embodiments of this application. Furthermore, the descriptions of each embodiment below have their own specific focus. For details not provided in one embodiment, please refer to the relevant descriptions of other embodiments.

[0046] Figure 2 This is a structural diagram of the wrench groove 10 in an embodiment of the present application; Figure 3This is a structural detail diagram of the wrench groove 10 in the embodiment of the present application, to clearly show the relevant dimensions of the wrench groove 10; Figure 2 and Figure 3 The wrench groove 10 provided in the present application includes a plurality of connected protrusions, which are arranged at equal angles on the inner side wall of the wrench groove 10 around the center line of the wrench groove 10; the protrusions protrude toward the radial outside of the wrench groove 10; in the cross section of the inner side wall, the protrusions include a first convex arc segment 11 and a second convex arc segment 12 that are connected.

[0047] Compared with the prior art, the multiple protrusions in the wrench groove 10 provided in the present application are continuous, and a recess is naturally formed between each two adjacent protrusions, so that the protrusions in the above-mentioned wrench groove 10 can transmit greater torque. At the same time, the multiple protrusions of the present application are continuous, that is, the arc length of the inscribed circle of the wrench groove 10 corresponding to each protrusion is longer, that is, the angle formed by the tangent of the first convex arc segment 11 and the tangent of the second convex arc segment 12 in each protrusion is relatively large, and the waste chips generated in the process of punching the wrench groove 10 are easily discharged. Therefore, the manufacturing difficulty and processing cost of the above-mentioned wrench groove 10 are reduced through the above-mentioned setting, and because the punching margin of the wrench groove 10 in the present application is small, when the above-mentioned wrench groove 10 is processed on the fastener, the impact force received by the fastener is smaller, that is, the vibration of the fastener is smaller, thereby reducing the risk of thread damage to the fastener during the processing of the above-mentioned wrench groove 10, thereby improving the fatigue performance and mechanical properties of the fastener.

[0048] In addition, the first convex arc segment 11 and the second convex arc segment 12 in each protrusion in the present application are both an arc. Since the arc is a regular shape, it can be positioned according to the center of the circle corresponding to the arc segment when processing the arc segment, or, when processing the arc segment, it can also be positioned according to the distance between the center of the twisting groove 10 and the center of the circle corresponding to the arc segment, so that the processing accuracy of the protrusion is guaranteed, and its manufacturing difficulty is reduced, thereby improving the processing efficiency of the twisting groove 10.

[0049] It will be appreciated that the wrench groove 10 is used on a fastener. The fastener can be made of a metal material. For aviation applications, the fastener can also be made of a metal with a high elastic limit and low plastic deformation, such as titanium alloy or other existing composite materials. Furthermore, the plurality of protrusions project radially outward from the wrench groove 10.

[0050] Continue to refer to Figure 2 and Figure 3The first convex arc segment 11 and the second convex arc segment 12 correspond to different centers of circles, and the radius R1 of the first convex arc segment 11 is not equal to the radius R2 of the second convex arc segment 12. Therefore, for different usage environments and different requirements for the installation torque and disassembly torque of the fastener, the present application makes the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 unequal, that is, there is a certain radius difference between the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12, which can provide a certain ratchet deflection angle for the tightening of the fastener, thereby making the fastener with the above-mentioned wrench groove 10 have a higher installation torque.

[0051] For example, there are six protrusions in the wrench groove 10 in the present application. Of course, the protrusions in the wrench groove 10 in the present application can also be four, five, six, seven, eight, or even more.

[0052] In some embodiments of the present application, on the cross section of the inner side wall, the protrusion further includes an outward convex arc transition section 13, the outward convex arc transition section 13 connecting the first convex arc section 11 and the second convex arc section 12, and the radius of the outward convex arc transition section 13 is much smaller than the radius of the first convex arc section 11, or much smaller than the radius of the second convex arc section 12, such as Figure 2 That is, the radius of the outward convex arc transition section 13 is very small.

[0053] Therefore, on the one hand, the outward convex arc transition section 13 can avoid the presence of a sharp angle between two adjacent first convex arc sections 11 and the second convex arc sections 12 in the same protrusion, thereby reducing or avoiding potential performance risks such as stress concentration and product cracking at the sharp angle, and at the same time further reducing the manufacturing and processing difficulty of the above-mentioned wrench groove 10 and the fastener having the above-mentioned wrench groove 10.

[0054] On the other hand, since the radius of the outward convex arc transition section 13 is very small, the protrusion is roughly triangular in structure. In this way, during actual use, when the fastener having the above-mentioned wrench groove 10 is tightened by a tightening tool, the protrusion in the above-mentioned wrench groove 10 can transmit a larger torque, thereby increasing the torsional strength of the wrench groove 10. Based on the above embodiment, when the radius of the first convex arc segment 11 is greater than the radius of the second convex arc segment 12, the ratio of the radius of the second convex arc segment 12 to the radius of the outer convex arc transition segment 13 is: (40~80):1; when the radius of the first convex arc segment 11 is smaller than the radius of the second convex arc segment 12, the ratio of the radius of the first convex arc segment 11 to the radius of the outer convex arc transition segment 13 is: (40~80):1, so as to ensure that the radius of the outer convex arc transition section 13 is much smaller than the radius of the first convex arc segment 11, or much smaller than the radius of the second convex arc segment 12, thereby further increasing the torsional strength of the wrench groove 10.

[0055] If the radius of the convex arc transition section 13 is less than 0.5 mm, it will increase the difficulty of processing the convex arc transition section 13. If the radius of the convex arc transition section 13 is greater than 2 mm, the arc lengths of the first convex arc section 11 and the second convex arc section 12 will be reduced, thereby reducing the contact area between the fastening tool and the protrusion, which is not conducive to increasing the torsional strength of the wrench groove 10. Therefore, in some preferred embodiments, the radius of the convex arc transition section 13 in this application ranges from 0.5 mm to 2 mm.

[0056] Based on the above embodiment, a plurality of concave arc transition sections 14 are further provided on the cross section of the inner side wall for connecting adjacent protrusions; the first convex arc section 11 of each protrusion is connected to the second convex arc section 12 of the adjacent protrusion through one of the concave arc transition sections 14; the second convex arc section 12 of each protrusion is connected to the first convex arc section 11 of the adjacent protrusion through another concave arc transition section 14, thereby converting the line contact between the fastening tool and the wrench groove 10 into surface contact between the fastening tool and the wrench groove 10, further increasing the contact area between the wrench groove 10 and the fastening tool, and thereby increasing the torsional strength of the wrench groove 10.

[0057] Similarly, the radius of the concave arc transition section 14 is much smaller than the radius of the first convex arc section, or much smaller than the radius of the second convex arc section.

[0058] Moreover, when the radius of the first convex arc segment 11 is greater than the radius of the second convex arc segment 12, the ratio of the radius of the second convex arc segment 12 to the radius of the concave arc transition segment 14 is: (40-80):1; when the radius of the first convex arc segment 11 is less than the radius of the second convex arc segment 12, the ratio of the radius of the first convex arc segment 11 to the radius of the concave arc transition segment 14 is: (40-80):1

[0059] For example, the radius of the concave arc transition section 14 also ranges from 0.5 mm to 2 mm.

[0060] It is understood that the proximal end of the first convex arc segment 11 (the end close to the centerline of the wrench groove 10 in the cross section of the wrench groove 10) is connected to the proximal end of the second convex arc segment 12 in the adjacent convex portion via an inwardly concave arc transition section 14, and the proximal end of the second convex arc segment 12 is connected to the proximal end of the first convex arc segment 11 in the adjacent convex portion via another inwardly concave arc transition section 14. The proximal ends refer to the ends of the first convex arc segment 11 and the second convex arc segment 12 close to the axial centerline of the wrench groove 10.

[0061] Similarly, "the first convex arc segment 11 in each of the above-mentioned protrusions is connected to the second convex arc segment 12 through an outer convex arc transition section 13" means that the distal end of the first convex arc segment 11 in each of the above-mentioned protrusions (the end away from the center line of the twisting groove 10 in the cross section of the twisting groove 10) is connected to the distal end of the second convex arc segment 12 through an outer convex arc transition section 13, wherein the aforementioned distal end refers to the end of the first convex arc segment 11 and the second convex arc segment 12 away from the radial inner side.

[0062] Continue to refer to Figure 2 and Figure 3 The circumscribed diameter D1 of the wrench groove 10 and the inscribed diameter D2 of the wrench groove 10 satisfy the following equation: D2 = (0.7-0.95) × D1. Therefore, a reasonable ratio between the circumscribed diameter D1 and the inscribed diameter D2 of the wrench groove 10 is selected based on the different requirements of different connection parts to ensure that the wrench groove 10 can withstand appropriate torque strength while also reducing the weight and processing difficulty of the fastener having the wrench groove 10. This is particularly important in weight-sensitive connection fields such as aerospace.

[0063] In some embodiments, the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 satisfy: D2 = (0.72 × D1), the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 satisfy: D2 = (0.78 × D1), the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 satisfy: D2 = (0.8 × D1), the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 satisfy: The inscribed circle diameter D2 of the groove 10 satisfies: D2 = (0.89×D1), the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 satisfy: D2 = (0.9×D1), the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 satisfy: D2 = (0.92×D1) or the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 satisfy: D2 = (0.93×D1).

[0064] It should be noted that the data on the proportional relationship between the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10 are only part of the data, not all the data on the proportional relationship between the circumscribed circle diameter D1 of the wrench groove 10 and the inscribed circle diameter D2 of the wrench groove 10.

[0065] In some embodiments of the present application, the angle α between the tangent of the first convex arc segment 11 and the tangent of the second convex arc segment 12 is 90°~150°. In the connection use environment of the fastener having the wrench groove 10, especially in the high vibration and high fatigue resistance use environment such as aerospace and nuclear power, the angle α between the tangent of the first convex arc segment 11 and the tangent of the second convex arc segment 12 is 90°~150°, which can ensure that the fastener with the wrench groove 10 has the best torque and the overall mechanical properties of the product.

[0066] It should be noted that the protrusions in the wrench groove 10 have the same shape and size in the extension direction of the center line of the wrench groove 10 , which simplifies the processing of the wrench groove 10 and reduces the manufacturing cost of the wrench groove 10 .

[0067] In addition, the present application also provides a fastener comprising a head and a stem, wherein the end surface of the head facing away from the stem or the end surface of the stem facing away from the head is provided with the wrench groove 10. For example, the fastener is usually a bolt or a countersunk screw.

[0068] Hereinafter, the wrench groove provided on the end surface of the head portion facing away from the rod portion or the end surface of the rod portion facing away from the head portion will be described in detail.

[0069] Example 1

[0070] The wrench groove 10 is provided on the end surface of the head portion of the fastener facing away from the rod portion.

[0071] Figure 4 1 is a schematic structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a bolt and the wrench groove is provided on the bolt head; Figure 5 yes Figure 4 Left view of; Figure 6 1 is a schematic structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a countersunk screw and the wrench groove is provided on the head of the countersunk screw; Figure 7 yes Figure 6 Left view of .

[0072] Reference Figures 2 to 7 The wrench groove 10 is provided on the end surface of the head portion of the fastener away from the rod portion, for example: a wrench groove 10 is provided on the end surface of the head 21 of the bolt 20 away from the rod portion 22 of the bolt 20, or a wrench groove 10 is provided on the end surface of the head 31 of the countersunk screw 30 away from the rod portion 32 of the countersunk screw 30, wherein the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.1~2) × R2, thereby ensuring that the fastener with the above-mentioned wrench groove 10 has a higher installation torque, thereby providing the fastener with the above-mentioned wrench groove 10 with a torque that better meets the use requirements.

[0073] In some embodiments, the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.2 × R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.35 × R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.43 × R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.43 × R2), The radius R2 of the two convex arc segments 12 satisfies: R1 = (1.5×R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.65×R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.8×R2) or the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.9×R2).

[0074] It should be noted that the above data on the proportional relationship between the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 only lists a part, not all the data on the proportional relationship between the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12.

[0075] In some embodiments of the present application, when the wrench groove 10 is provided on the end face of the head portion of the fastener facing away from the rod portion, and the number of the protrusions is an even number, the distance L between the two symmetrically arranged protrusions satisfies: L=R1 / (0.5~1), thereby adjusting the distance L between the two symmetrically arranged protrusions and thereby adjusting the size of the ratchet angle formed by the first convex arc segment 11 and the second convex arc segment 12, thereby ensuring that a torque that better meets the use requirements is provided.

[0076] In some embodiments, the distance L between the two symmetrically arranged protrusions satisfies: L = (R1 / 0.6), the distance L between the two symmetrically arranged protrusions = (R1 / 0.65), the distance L between the two symmetrically arranged protrusions = (R1 / 0.72), the distance L between the two symmetrically arranged protrusions = (R1 / 0.78), the distance L between the two symmetrically arranged protrusions = (R1 / 0.83), the distance L between the two symmetrically arranged protrusions = (R1 / 0.88) or the distance L between the two symmetrically arranged protrusions = (R1 / 0.95).

[0077] It should be noted that the above data on the distance L between the two symmetrically arranged protrusions only lists a part, and not all the data on the distance L between the two symmetrically arranged protrusions.

[0078] Example 2

[0079] The wrench groove 10 ′ is provided on the end surface of the rod portion of the fastener facing away from the head portion.

[0080] Figure 8 1 is a structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a bolt and the wrench groove is provided on the bolt shank; Figure 9 yes Figure 8 Left view of; Figure 10 1 is a schematic structural diagram of a fastener in an embodiment of the present application, wherein the fastener is a countersunk screw and the wrench groove is provided on the shank of the countersunk screw; Figure 11 yes Figure 10 Left view of .

[0081] Reference Figure 3 、 Figures 8 to 11The wrench groove 10' is provided on the end surface of the shank away from the head in the above-mentioned fastener. For example, a wrench groove 10' is provided on the end surface of the shank 22 of the bolt 20 away from the head 21 of the bolt 20, or a wrench groove 10' is provided on the end surface of the shank 32 of the countersunk screw 30 away from the head 31 of the countersunk screw 30, wherein the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R2 = (1.1~1.5)×R1. Since the diameter of the shank in the fastener is usually smaller than the diameter of the head, the value of the radius R1 of the first convex arc segment 11 is slightly smaller than the value of the radius R1 of the first convex arc segment 11 when the above-mentioned wrench groove 10 is located at the head of the fastener, thereby ensuring that the fastener with the above-mentioned wrench groove 10 has a higher installation torque, thereby providing the fastener with the above-mentioned wrench groove 10' with a torque that better meets the use requirements.

[0082] Based on the above embodiments, the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.15×R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.2×R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.27×R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.32×R2), the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.4×R2), or the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 satisfy: R1 = (1.45×R2).

[0083] It should be noted that the above data on the proportional relationship between the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12 only lists a part, not all the data on the proportional relationship between the radius R1 of the first convex arc segment 11 and the radius R2 of the second convex arc segment 12.

[0084] In some embodiments of the present application, when the wrench groove 10' is provided on the end surface of the rod portion facing away from the head portion, and the number of the protrusions is an even number, the distance L between the two symmetrically arranged protrusions satisfies: L=R1 / (1~1.5). By adjusting the distance L between the two symmetrically arranged protrusions, the size of the ratchet angle formed by the first convex arc segment 11 and the second convex arc segment 12 can be adjusted to ensure that a torque that better meets the use requirements is provided.

[0085] Based on the above embodiments, the distance L between the two symmetrically arranged protrusions is (R1 / 1.1), the distance L between the two symmetrically arranged protrusions is (R1 / 1.18), the distance L between the two symmetrically arranged protrusions is (R1 / 1.20), the distance L between the two symmetrically arranged protrusions is (R1 / 1.26), the distance L between the two symmetrically arranged protrusions is (R1 / 1.3), the distance L between the two symmetrically arranged protrusions is (R1 / 1.33), the distance L between the two symmetrically arranged protrusions is (R1 / 1.36), the distance L between the two symmetrically arranged protrusions is (R1 / 1.4) or the distance L between the two symmetrically arranged protrusions is (R1 / 1.48).

[0086] It should be noted that the above data on the distance L between the two symmetrically arranged protrusions only lists a part, and not all the data on the distance L between the two symmetrically arranged protrusions.

[0087] At present, test results show that the torque of the fastener with the above-mentioned wrench groove 10 of the present application is increased by about 80% compared with the traditional high-locking bolts of the same specifications, and the installation success rate reaches 100%.

[0088] In addition, the end of the rod portion of the fastener in the embodiment of the present application is provided with a threaded section at one end away from the head portion, for achieving a threaded connection with another component.

[0089] At the same time, the present application also provides a fastening tool including a fitting portion, which is used to cooperate with the wrench groove 10 (wrench groove 10') in the above-mentioned fastener. The shape of the fitting portion is configured relative to the shape of the wrench groove 10 (wrench groove 10'). When the fitting portion and the wrench groove 10 (wrench groove 10') are fitted with each other and the fastening tool rotates around the center line of the wrench groove 10 (wrench groove 10'), the fitting portion transmits the tightening torque to the fastener through the protrusion of the wrench groove 10 (wrench groove 10').

[0090] To this end, since the fastening tool of the present application includes a fitting portion that cooperates with the wrench groove 10 (wrench groove 10') in the above-mentioned fastener, the fitting portion transmits the tightening torque to the fastener through the protruding portion of the wrench groove 10 (wrench groove 10'), and the fitting portion adopts the same structure as the above-mentioned wrench groove 10 (wrench groove 10'), the two can solve the same technical problem and achieve the same expected effect.

[0091] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0092] The above is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims. In addition, the specification uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core ideas of the present application. The content of this specification should not be understood as limiting the present application.

Claims

1. A wrench groove, characterized in that: comprising a plurality of connected protrusions, A plurality of protrusions are arranged on the inner side wall of the wrench groove at equal angles around the center line of the wrench groove; the protrusions protrude toward the radial outside of the wrench groove; In the cross section of the inner side wall, the protrusion includes a first convex arc segment and a second convex arc segment connected to each other; The first convex arc segment and the second convex arc segment correspond to different centers of circles, and the radius of the first convex arc segment is not equal to the radius of the second convex arc segment; In the cross section of the inner sidewall, the protrusion further includes an outward convex arc transition section, the outward convex arc transition section connecting the first convex arc section and the second convex arc section, and the radius of the outward convex arc transition section is much smaller than the radius of the first convex arc section, or much smaller than the radius of the second convex arc section; When the radius of the first convex arc segment is greater than the radius of the second convex arc segment, the ratio of the radius of the second convex arc segment to the radius of the outer convex arc transition segment is: (40-80):1; When the radius of the first convex arc segment is smaller than the radius of the second convex arc segment, the ratio of the radius of the first convex arc segment to the radius of the outer convex arc transition segment is: (40-80):1; The angle α between the tangent of the first convex arc segment and the tangent of the second convex arc segment is 90° to 150°; The radius R1 of the first convex arc segment and the radius R2 of the second convex arc segment satisfy: R1=(1.1-2)×R2, or R2=(1.1-1.5)×R1.

2. The wrench slot according to claim 1, characterized in that: The cross section of the inner side wall is also provided with a plurality of concave arc transition sections for connecting adjacent protrusions; The first convex arc segment of each protruding portion is connected to the second convex arc segment of the adjacent protruding portion through the concave arc transition segment; The second convex arc segment of each protruding portion is connected to the first convex arc segment of the adjacent protruding portion through the concave arc transition segment.

3. The wrench slot according to claim 1, characterized in that: The circumscribed circle diameter D1 of the wrench groove and the inscribed circle diameter D2 of the wrench groove satisfy the following: D2 = (0.7-0.95) × D1.

4. The wrench slot according to claim 1, characterized in that: The protrusions have the same shape and size in the extending direction of the center line of the wrench groove.

5. A fastener, characterized in that: It comprises a head and a rod, wherein the end surface of the head facing away from the rod or the end surface of the rod facing away from the head is provided with a wrench groove as described in any one of claims 1 to 4; When the wrench groove is provided on the end surface of the head portion facing away from the rod portion, the radius R1 of the first convex arc segment and the radius R2 of the second convex arc segment satisfy the following: R1=(1.1-2)×R2.

6. The fastener according to claim 5, wherein: The wrench groove is provided on the end surface of the head portion facing away from the rod portion, and when the number of the protrusions is an even number, the distance L between two symmetrically arranged protrusions satisfies: L=R1 / (0.5~1).

7. The fastener according to claim 6, wherein: When the wrench groove is provided on the end surface of the rod portion facing away from the head portion, the radius R1 of the first convex arc segment and the radius R2 of the second convex arc segment satisfy: R2=(1.1-1.5)×R1.

8. The fastener according to claim 5 or 7, characterized in that: When the wrench groove is provided on the end surface of the rod away from the head and the number of the protrusions is an even number, the distance L between two symmetrically arranged protrusions satisfies: L=R1 / (1-1.5).

9. The fastener according to claim 5, wherein: The rod portion is provided with a threaded section.

10. The fastener according to claim 5 or 9, characterized in that: The fastener is a bolt or a countersunk screw.

11. A fastening tool, characterized in that: It includes at least one engaging portion for cooperating with the wrench groove in the fastener according to any one of claims 5 to 10, the shape of the engaging portion is arranged relative to the shape of the wrench groove, and when the engaging portion and the wrench groove are engaged with each other and the fastening tool rotates around the center line of the wrench groove, the engaging portion transmits the tightening torque to the fastener through the protrusion of the wrench groove.

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