Vehicle tow hook assembly

Abstract

The utility model discloses a vehicle tow hook assembly which comprises a beam body, a tow hook assembly and a connecting plate connecting the beam body and the tow hook assembly, the connecting plate is provided with a connecting groove configured to be matched with the outer wall of the beam body, and the portion, beside the connecting groove, of the connecting plate is fixedly welded to the beam body; the tow hook assembly is detachably connected with the connecting plate through a fixing piece penetrating through the mounting hole; and the connecting plate is provided with at least one unloading hole between the connecting groove and the mounting hole. The connecting plate has the advantage that the problem of stress concentration of a welding area and a bolt fixing area of an existing connecting plate is solved. The geometric characteristics of the hole are utilized to guide stress streamline redistribution, high stress originally concentrated on a local part is dispersed to a larger area, and the stress gradient of a welding area and the edge of the bolt hole is obviously reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to vehicle connecting piece technical field, concretely relates to a vehicle trailer hook assembly. BACKGROUND

[0002] In the design of vehicle trailer hook and other bearing structures, the support assembly as the key component connecting the vehicle frame and the trailer hook, its stress distribution characteristics directly affect the reliability and service life of the overall structure. In the traditional design, in order to reduce the stress concentration of the welding area and the bolt fixing area, the way of increasing the thickness of the connecting plate or local strengthening is usually adopted. However, this kind of method has obvious defects:

[0003] I. Space limitation: increasing the thickness of the plate or strengthening the structure is easy to cause the interference between the support assembly and other components, especially in the compact layout of the vehicle chassis design, the installation space is limited, and the problem is particularly prominent;

[0004] II. Weight and cost increase: material redundancy not only violates the lightweight design trend, but also increases the production cost;

[0005] III. Limited effect of stress concentration relief: simple structural reinforcement may transfer stress to other weak areas, and cannot fundamentally optimize the stress distribution. INVENTION CONTENTS

[0006] The utility model aims at providing a kind of vehicle trailer hook assembly, can effectively solve the problem of stress concentration of existing connecting plate in welding area and bolt fixing area.

[0007] To solve the above technical problems, the utility model is realized by the following technical solutions:

[0008] A kind of vehicle trailer hook assembly, including beam body, trailer hook component and the connecting plate connecting beam body and trailer hook component, connecting plate is equipped with:

[0009] Connecting groove is configured to be adapted to the outer wall of the beam body, and the connecting plate beside the connecting groove is welded and fixed with the beam body;And

[0010] Mounting hole, the trailer hook component is detachably connected with the connecting plate by the fixing piece passing through the mounting hole;

[0011] The connecting plate is provided with at least one unloading hole between the connecting groove and the mounting hole.

[0012] In the above-mentioned kind of vehicle trailer hook assembly, the unloading hole is concave structure, and the concave surface faces the mounting hole;The concave structure includes at least one arc segment, and the both ends of the arc segment extend to the edge of the connecting plate to form an opening.

[0013] In the vehicle trailer hook assembly, the top of the arc segment is located on the line connecting the center axis of the connecting groove and the center axis of the mounting hole.

[0014] In the vehicle trailer hook assembly, the two ends of the arc segment are connected with linear segments, and the linear segments gradually move away from the connecting groove and the mounting hole.

[0015] In the vehicle trailer hook assembly, the width of the linear segment gradually increases from the one end connected with the arc segment to the one end away from the arc segment.

[0016] In the vehicle trailer hook assembly, the arc segment is a circular arc with the center located on the axis of the mounting hole.

[0017] In the vehicle trailer hook assembly, the projection of the mounting hole on the plate body is located in the closed area formed by the two ends of the unloading hole and the unloading hole.

[0018] In the vehicle trailer hook assembly, the unloading hole is arranged between the welding heat affected zone and the pre-tightening force concentration area of the fixing member.

[0019] In the vehicle trailer hook assembly, the unloading hole is arranged between the welding heat affected zone and the pre-tightening force concentration area of the fixing member.

[0020] In the vehicle trailer hook assembly, the inner wall edge of the unloading hole is provided with a fillet transition structure.

[0021] Compared with the prior art, the vehicle trailer hook assembly has the following advantages:

[0022] By arranging at least one unloading hole between the connecting groove and the mounting hole on the connecting plate, the stress concentration problem of the welding area and the bolt fixing area of the connecting plate is solved. Through active structure optimization, the unloading hole is arranged in the high-risk stress concentration area between the welding area and the bolt hole of the connecting plate, and the stress flow lines are redistributed by using the geometric characteristics of the hole. This design discards the conservative idea of "replacing strength with material", and realizes the essential improvement of mechanical properties through spatial topology optimization. The position of the unloading hole is located in the key transition area of stress conduction, which effectively breaks the original rigid force transmission path and forces the stress flow lines to redistribute around the unloading hole, significantly reducing the stress gradient of the welding area and the edge of the bolt hole. The unloading hole removes the local non-critical bearing material, realizes structure weight reduction under the premise of ensuring overall stiffness, and replaces "addition" with "subtraction", avoiding redundant material accumulation, and lightweight structure can reduce vehicle energy consumption, indirectly improving the overall energy efficiency of the trailer system. The introduction of the unloading hole enhances the local deformation capacity of the connecting plate, allowing the structure to absorb dynamic load energy through controllable deformation within the elastic range, effectively buffering the instantaneous impact and avoiding brittle fracture caused by sudden stress rise.

[0023] Further, the unloading hole is a concave structure, and the concave surface faces the mounting hole; the concave structure comprises at least one arc segment, and two ends of the arc segment extend to the edges of the connecting plate to form openings. The structure of the above-mentioned unloading hole makes the stress flow line smoother, and when the bracket is stressed, the arc segment can disperse the concentrated stress along the arc profile, avoiding excessive stress concentration in the local area. When stress occurs in the welding and fixed connection area, the unloading hole of the concave structure can guide the stress to diffuse uniformly around, improve the stress distribution, reduce the stress concentration phenomenon, and improve the carrying capacity and reliability of the bracket assembly. This concave structure design can not only disperse stress, but also maintain the stability of the bracket structure. The concave structure has good mechanical properties and will not excessively reduce the overall structural strength of the bracket in the process of weakening the rigidity of the connecting plate to disperse stress. Compared with sharp or irregularly shaped openings, the concave structure unloading hole causes less damage to the bracket structure and can maintain the overall stability of the bracket. During vehicle driving, the trailer hook bracket will be subjected to various complex external forces. The unloading hole with the arc segment of the concave structure can disperse stress and ensure that the bracket can still stably connect the beam body and the trailer hook assembly, thereby ensuring the normal work of the trailer hook assembly.

[0024] Further, the arc top of the arc segment is located on the line connecting the center axis of the connecting groove and the center axis of the mounting hole. When the bracket is subjected to force from the beam body and the trailer hook assembly, since the arc top of the unloading hole is at this special position, stress can be dispersed more uniformly along the direction of the center line connecting the connecting groove, the unloading hole and the mounting hole, avoiding excessive stress concentration in the local area, thereby effectively reducing the stress concentration phenomenon and improving the carrying capacity and reliability of the bracket assembly.

[0025] Further, the two ends of the arc segment are respectively connected with linear segments, and the linear segments gradually move away from the connecting groove and the mounting hole. When the bracket is subjected to stress from the connecting groove and the mounting hole, the arc segment can smoothly guide the stress to the linear segment by virtue of its smooth transition feature, and the design that the linear segments gradually move away from the connecting groove and the mounting hole enables the stress to diffuse to a wider area, avoiding excessive stress concentration in the local area.

[0026] Further, the width of the linear segment gradually increases from the end connected with the arc segment to the end away from the arc segment. This variable-width design optimizes the stress dispersion path, and while ensuring stress dispersion and structural strength, it helps to realize product lightweighting. Compared with the linear segment with uniform width, this variable-width design reduces the use of materials in the area with smaller stress and increases the materials in the area with larger stress to ensure the strength, so that the material distribution is more reasonable.

[0027] Further, the arc-shaped section is a circular arc with a center located on the axis of the mounting hole. When the bracket assembly bears stress from the connecting groove and the trailer hook assembly, the stress can be evenly dispersed through the circular arc section of the unloading hole with the axis of the mounting hole as the center.

[0028] Further, the projection of the mounting hole on the plate body is located within the closed area enclosed by the line connecting the two ends of the unloading hole and the unloading hole, so that the fixed part pre-tightening force field and the unloading hole stress release area are superimposed and optimized to reduce the main stress peak.

[0029] Further, the unloading hole is arranged in the area between the welding heat affected zone and the fixed part pre-tightening force concentration area. Arranging the unloading hole between the two areas can accurately optimize the high stress area, and the unloading hole can directly act on the area with serious stress concentration, avoiding ineffective design, greatly improving the stress optimization effect and efficiency of the bracket assembly, making the stress distribution of the entire bracket more uniform, and significantly improving the mechanical properties and carrying capacity of the bracket assembly. The stress conditions of the welding heat affected zone and the fixed part pre-tightening force concentration area are complex and highly concentrated, and the unloading hole between the two can better play the role of locally weakening the rigidity of the connecting plate, effectively dispersing stress, breaking the stress concentration distribution state, and guiding stress redistribution.

[0030] Further, the unloading hole is arranged in the area between the welding heat affected zone and the fixed part pre-tightening force concentration area. Arranging the unloading hole between the two areas can accurately optimize the high stress area, and the unloading hole can directly act on the area with serious stress concentration, avoiding ineffective design, greatly improving the stress optimization effect and efficiency of the bracket assembly, making the stress distribution of the entire bracket more uniform, and significantly improving the mechanical properties and carrying capacity of the bracket assembly. The stress conditions of the welding heat affected zone and the fixed part pre-tightening force concentration area are complex and highly concentrated, and the unloading hole between the two can better play the role of locally weakening the rigidity of the connecting plate, effectively dispersing stress, breaking the stress concentration distribution state, and guiding stress redistribution.

[0031] Further, the inner wall edge of the unloading hole is provided with a round corner transition structure. The sharp corners of the inner wall edge of the unloading hole can cause the stress flow lines to sharply turn, forming local stress peaks. The round corner transition structure can smooth the stress flow line turning, eliminate stress concentration points, and avoid stress concentration. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a structural schematic view of the connecting plate in the utility model;

[0033] Figure 2 is a structural schematic view of a vehicle trailer hook assembly in the utility model;

[0034] Figure 3 is Figure 2 is an A-A sectional view in the utility model. BRIEF DESCRIPTION OF DRAWINGS:

[0036] The connecting plate 10, the connecting groove 11, the mounting hole 12, the unloading hole 13, the circular arc segment 131, the straight line segment 132, the beam body 20, the trailer hook assembly 30. DETAILED DESCRIPTION

[0037] The utility model provides a vehicle trailer hook assembly, which comprises a beam body 20, a trailer hook assembly 30 and a connecting plate 10 connecting the beam body 20 and the trailer hook assembly 30, wherein the connecting plate 10 is provided with a connecting groove 11 matched with the outer wall of the beam body 20, and the connecting plate 10 beside the connecting groove 11 is welded and fixed with the beam body 20; and a mounting hole 12, the trailer hook assembly 30 is detachably connected with the connecting plate 10 through a fixing piece penetrating through the mounting hole 12; and at least one unloading hole 13 is arranged between the connecting groove 11 and the mounting hole 12 of the connecting plate 10.

[0038] By arranging at least one unloading hole 13 between the connecting groove 11 and the mounting hole of the connecting plate 10, the problem of stress concentration in the welding area and the bolt fixing area of the connecting plate 10 is solved. Through active structure optimization, the unloading hole 13 is arranged in the high-risk area of stress concentration between the welding area and the bolt hole of the connecting plate 10, the stress flow lines are redistributed by using the geometric characteristics of the hole, and the high stress originally concentrated in the local area is dispersed to a larger area. This design abandons the conservative idea of “replacing strength with material”, and realizes the essential improvement of mechanical properties through spatial topology optimization. The position of the unloading hole 13 is located in the key transition area of stress conduction, which effectively breaks the original rigid force transmission path and forces the stress flow lines to redistribute around the unloading hole 13, thereby significantly reducing the stress gradient of the welding area and the edge of the bolt hole. The unloading hole 13 removes the local non-critical bearing material, realizes structure weight reduction under the premise of ensuring overall stiffness, and replaces “addition” with “subtraction”, avoids redundant material accumulation, and reduces the energy consumption of the vehicle, thereby indirectly improving the overall energy efficiency of the trailer system. The introduction of the unloading hole 13 enhances the local deformation capacity of the connecting plate 10, allows the structure to absorb dynamic load energy through controllable deformation within the elastic range, effectively buffers the instantaneous impact, and avoids brittle fracture caused by sudden stress rise.

[0039] The embodiments of the utility model will be described in detail below, and examples of the embodiments are shown in the drawings. The embodiments described below by referring to the drawings are exemplary and are intended to explain the utility model, and cannot be understood as a limitation of the utility model.

[0040] In the description of the utility model, it is understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the utility model.

[0041] In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the utility model, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0042] In the utility model, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected or in communication with each other; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise specifically limited. For ordinary skilled persons in the art, the specific meaning of the above terms in the utility model can be understood according to the specific situation.

[0043] Reference Figures 1 to 3 For the embodiment of the utility model vehicle trailer hook assembly, the vehicle trailer assembly comprises a beam body 20, a trailer hook assembly 30 and a connecting plate 10 connecting the beam body 20 and the trailer hook assembly 30. The specific shape of the connecting plate 10 is set according to the setting position and the components that the connecting plate 10 needs to connect. The connecting plate 10 is provided with a connecting groove 11 and a mounting hole 12. The connecting groove 11 is matched with the outer wall of the beam body 20, for example, the beam body 20 is cylindrical, and the connecting groove 11 is arc-shaped. The cross section of the beam body 20 is rectangular, and the cross section of the connecting groove 11 is also rectangular, so that the connecting groove 11 is matched with the beam body 20, the contact area of the connecting groove 11 and the beam body 20 is increased, and then the connecting plate 10 beside the connecting groove 11 is connected with the beam body 20 by welding. The mounting seat of the trailer hook assembly 30 is detachably connected with the connecting plate 10 through the fixing piece passing through the mounting hole 12. The fixing piece generally adopts the structure of bolt and nut matching, so as to facilitate the mounting and dismounting of the trailer hook assembly 30.

[0044] At least one unloading hole 13 is arranged between the connecting groove 11 and the mounting hole 12 on the connecting plate 10, the unloading hole 13 guides stress flow lines to be redistributed by the geometric characteristics of the hole, so that the stress can be redistributed along the edge of the unloading hole 13, avoiding excessive concentration of stress in a local area, dispersing the stress to a larger area, thereby reducing the local stress peak, and the arrangement of the unloading hole 13 also locally weakens the rigidity of the connecting plate 10, and can also achieve the purpose of dispersing welding and fixing the stress concentration area. That is, in the scheme of the utility model, the problem of stress concentration is not solved by increasing the thickness of the connecting plate 10 or locally strengthening, but by opening a hole in the connecting plate 10 to disperse the stress. Compared with the traditional thickening support to reduce stress concentration, the unloading hole 13 does not need to increase the thickness of the plate, avoids the risk of interference, realizes the lightweight of the product, reduces the design redundancy and cost, and the structure of the unloading hole 13 is simple and the production process is easy to implement, which enables efficient batch production in actual production, improves production efficiency, reduces production cost, and has good economic benefits.

[0045] Further, the unloading hole 13 can be arranged in the area between the welding heat affected zone and the fixing piece pre-tightening force concentration area, which can accurately optimize the high stress area, and the unloading hole 13 can directly act on the area with serious stress concentration, avoiding invalid design and greatly improving the effect and efficiency of stress optimization of the support assembly. For the determination of the welding heat affected zone, the welding heat affected zone range can be obtained according to the heat diffusion equation, combined with the material thermal diffusion coefficient and high temperature duration at the preliminary design; or the position of the welding heat affected zone can be determined by using metallographic detection method or infrared thermal imaging method. The fixing piece pre-tightening force concentration area can be calculated by using the stress attenuation formula in the elastic mechanics model; or the range of the fixing piece pre-tightening force concentration area can be determined by using the strain gauge measurement method.

[0046] For the shape of the unloading hole 13, in the embodiment, the unloading hole 13 is a concave structure, and the concave surface faces the mounting hole 12, the concave structure includes at least one arc segment, and the two ends of the arc segment extend to the edge of the connecting plate to form an opening. The arc structure can more effectively guide the stress flow lines and reduce stress concentration. The design of the concave surface facing the mounting hole 12 can disperse the stress from the high stress area around the welding and mounting hole to the low stress area, thereby reducing the peak stress, and the arc structure can maintain or enhance the local strength while reducing the use of materials, avoiding the loss of strength caused by the opening. In processing, the arc structure is also easier to realize by stamping or laser cutting process.

[0047] Further, the arc top of the arc segment of the unloading hole 13 is located on the line connecting the central axis of the connecting groove 11 and the central axis of the mounting hole 12. In the embodiment, the connecting groove 11 is a circular arc groove, and the central axis of the connecting groove 11 is the axis passing the center of the connecting groove 11. The mounting hole 12 is generally a circular hole. The arc top of the unloading hole 13 is arranged on the line connecting the central axis of the connecting groove 11 and the central axis of the mounting hole 12, the structure of the symmetric stress field of the component, the bending stress field of the connecting groove 11 and the tensile stress field of the unloading hole 13 form orthogonal superposition, and the measured equivalent stress is obviously reduced relative to the arc top of the unloading hole 13.

[0048] In addition, the opening profile of the unloading hole 13 is an arc structure, and the entire unloading hole 13 can be a circular arc. Although such a structure can also reduce the problem of stress concentration, stress concentration points are still prone to occur. In order to further reduce the stress concentration points, in the embodiment, the unloading hole 13 includes the arc segment 131, and a straight segment 132 is connected to each end of the arc segment 131, and the straight segment 132 gradually moves away from the connecting groove 11 and the mounting hole 12. Not only does this further reduce the stress concentration points, but the added straight segment 132 can generate a secondary stress gradient, greatly reducing the residual stress.

[0049] Further, the width of the straight segment 132 gradually increases from one end connected to the arc segment 131 to the other end away from the arc segment 131. Compared with the straight segment 132 with uniform width, this variable width design reduces material usage in areas with less stress and increases material in areas with more stress to ensure strength, making the material distribution more reasonable. When stress is transmitted from the arc segment 131 to the straight segment 132, the stress bearing area increases as the width of the straight segment 132 increases. The larger bearing area allows the stress to be more evenly distributed, avoiding stress concentration in local areas, thereby improving the overall stress dispersion effect of the bracket assembly. In addition, the wider part can withstand more stress, improving the local carrying capacity of the bracket without increasing the overall material usage.

[0050] Since the unloading hole 13 includes the arc segment 131, the center of the arc segment 131 can also be arranged on the axis of the mounting hole 12. The coaxial center of the arc segment 131 allows the circumferential stress of the unloading hole 13 and the radial stress of the mounting hole 12 to form orthogonal superposition, thereby reducing the maximum equivalent stress. When the bracket assembly bears stress transmitted from the connecting groove 11 and the mounting seat of the trailer hook assembly 30, the stress can be more evenly distributed through the arc segment 131 of the unloading hole 13 with the axis of the mounting hole 12 as the center.

[0051] On the basis of the above-mentioned embodiments, the projection of the mounting hole 12 on the connecting plate 10 along the axis is located in the closed area enclosed by the connecting line of the two ends of the unloading hole 13 and the unloading hole 13, and the position of the mounting hole 12 is closer to the central area of the unloading hole 13, so that the stress can be more evenly distributed when stressed, reducing stress concentration. At the same time, the closed area can form a more stable support structure to improve the overall rigidity. The projection of the mounting hole 12 is arranged in the enclosed area of the unloading hole 13, which makes full use of the space of the bracket connecting plate 10 and avoids redundant structure design, and realizes efficient integration of the functions of various components in the limited bracket space.

[0052] The above embodiments are all described by taking one unloading hole 13 as an example, and multiple unloading holes 13 can also be arranged to form the above shape. The unloading hole 13 with the same area is arranged on the connecting plate 10, and the multiple unloading holes 13 are arranged at intervals, which can increase the strength of the connecting plate 10 and also consider the stress dispersion effect, and the multiple unloading holes 13 can play a backup and complementary role. Even if one or several unloading holes 13 are partially disabled due to unexpected circumstances, the other unloading holes 13 can still continue to disperse stress and maintain the stress balance of the bracket, ensuring the stability of the bracket structure. In the long-term use of the trailer hook bracket, it is inevitable to be subjected to vibration, impact and other effects, and the design of multiple unloading holes 13 can effectively reduce the risk of failure of the entire bracket due to damage of individual unloading holes 13, and improve the reliability of the bracket assembly under complex working conditions.

[0053] In addition to arranging the unloading hole 13 into an arc-shaped structure, the unloading hole 13 can also be arranged into a long strip shape or other structures that are beneficial to reducing stress concentration between the connecting groove 11 and the mounting hole 12.

[0054] Through the above-mentioned embodiments, the conservative idea of "exchanging strength with material" is abandoned, and the mechanical properties are essentially improved through spatial topology optimization. The position of the unloading hole 13 is located in the key transition area of stress conduction, which effectively breaks the original rigid force transmission path and forces the stress flow lines to redistribute around the unloading hole 13, significantly reducing the stress gradient of the welding area and the edge of the bolt hole.

[0055] The above-mentioned is only a specific embodiment of the present application, but the technical features of the present application are not limited thereto, and any person skilled in the art in the field of the present application can make changes or modifications, which are all covered in the patent scope of the present application.

Claims

1. A vehicle trailer hitch assembly, characterized by, The connecting plate is provided with: a connecting groove configured to be fitted with the outer wall of the beam body, the connecting plate beside the connecting groove being welded and fixed with the beam body; and a mounting hole, the trailer hook assembly being detachably connected with the connecting plate through a fixing member penetrating through the mounting hole; the connecting plate being provided with at least one unloading hole between the connecting groove and the mounting hole.

2. A vehicle trailer hitch assembly as claimed in claim 1, wherein, The unloading hole is a concave structure, and the concave surface faces the mounting hole; the concave structure comprises at least one arc segment, both ends of the arc segment extending to the edge of the connecting plate to form an opening.

3. A vehicle trailer hitch assembly as defined in claim 2, wherein, The arc top of the arc segment is located on the connecting line of the central axis of the connecting groove and the central axis of the mounting hole.

4. A vehicle trailer hitch assembly as defined in claim 2, wherein, Both ends of the arc segment are respectively connected with a straight segment, and the straight segment gradually moves away from the connecting groove and the mounting hole.

5. A vehicle trailer hitch assembly as defined in claim 4, wherein, The width of the straight segment gradually increases from one end connected with the arc segment to the other end away from the arc segment.

6. A vehicle trailer hitch assembly as defined in claim 2, wherein, The arc segment is a circular arc, and the center of the circular arc is located on the axis of the mounting hole.

7. A vehicle trailer hitch assembly as claimed in any one of claims 2 to 6, characterised in that, The projection of the mounting hole on the plate body is located in the closed area jointly enclosed by the connecting line of both ends of the unloading hole and the unloading hole.

8. A vehicle trailer hitch assembly as defined in claim 1, wherein, The unloading hole is arranged in the region between the welding heat affected zone and the pre-tightening force concentration region of the fixing member.

9. A vehicle trailer hitch assembly as defined in claim 1, wherein, There are multiple unloading holes, and the unloading holes are arranged at intervals.

10. A vehicle trailer hitch assembly as defined in claim 1, wherein, The inner wall edge of the unloading hole is provided with a round corner transition structure.

Images