Patent Description:
Fasteners can connect multiple components together, such as interior parts, frames, and panels of a vehicle. A first component is first connected to a fastener when connected, and then the fastener connected to the first component is mounted at a corresponding position of a second component; or the fastener is first mounted at a corresponding position of the second component, and then the fastener is connected to the first component, so that the first component and the second component are connected to each other. For example, in an application, a vehicle wire clamp needs to be connected to a body sheet metal by a using fastener such that an interior panel is securely connected to the body sheet metal. A fastening clamp is known from <CIT>.

The present application provides a fastening clamp according to claim <NUM>, used for connecting a first component to a second component having a connecting post, including: a substrate on which a mounting hole is provided; at least two first retaining legs, and at least two second retaining legs, where the mounting hole is used to receive the connecting post of the second component, proximal ends of the at least two first retaining legs are connected to an edge of the mounting hole and extend obliquely from one side of the substrate towards one another in a direction away from the substrate, the at least two first retaining legs are resilient and configured to deflect about the proximal ends of the at least two first retaining legs, proximal ends of the at least two second retaining legs are connected to the edge of the mounting hole and extend obliquely from one side of the substrate towards one another in a direction away from the substrate, and the at least two first retaining legs and the at least two second retaining legs are on the same side of the substrate; where distal ends of the at least two second retaining legs are closer to the substrate than distal ends of the two first retaining legs, and the at least two first retaining legs and the at least two second retaining legs are configured to be able to collectively retain the connecting post of the second component in the mounting hole.

According to the fastening clamp described above, the at least two second retaining legs are staggered with the at least two first retaining legs about the mounting hole.

According to the fastening clamp described above, the at least two second retaining legs and the at least two first retaining legs are arranged along a circumferential direction, the fastening clamp being clampable on the cylindrical connecting post of the second component and rotating relative to the connecting post of the second component, the at least two second retaining legs being in contact with a sidewall of the connecting post of the second component.

According to the fastening clamp described above, each of the at least two first retaining legs and each of the at least two second retaining legs have a first contact and a second contact, respectively, the first contact being capable of contacting the second contact and the connecting post of the second component, and the first contact and the second contact extending helically around a centerline of the mounting hole.

According to the fastening clamp described above, a distance between the first contact and the centerline of the mounting hole is greater than a distance between the second contact and the centerline of the mounting hole.

According to the fastening clamp described above, the substrate has a first side and a second side, the at least two second retaining legs and the at least two first retaining legs extend outwardly from the first side, and the second side of the substrate has an anti-release structure.

According to the fastening clamp described above, the substrate has a front side and a back side, the fastener is inserted into a mounting component in a direction from the front side to the back side, the anti-release structure is a convex portion protruding from a surface of the second side, and the convex portion tapers and gradually becomes thicker in the direction from the front side to the back side.

According to the fastening clamp described above, the fastening clamp is integrally made of a metallic material.

According to the fastening clamp described above, hardness of the first contact and the second contact is greater than hardness of the connecting post of the second component.

According to the fastening clamp described above, a front side of the substrate has a front side flap bent inwardly from an edge of the front side, and the front side flap extends in the same direction as the substrate.

According to the fastening clamp described above, the back side of the substrate has a back side flap extending from an edge of the back side in a direction away from the first side of the substrate to form a stop portion.

According to the fastening clamp described above, the substrate has a stiffener protruding from a surface of the first side of the substrate, the stiffener is proximate to the back side of the substrate, and the stiffener is an arc curved toward a centerline of the mounting hole of the substrate.

The present application also provides a fastening clamp assembly, including: the fastening clamp described above and a connection seat; where the connection seat has a pair of receiving slots and a bottom, both sides of the substrate being able to enter the pair of receiving slots respectively to restrict movement of the fastening clamp in a direction perpendicular to the substrate; the bottom having an opening that aligns with the mounting hole when the fastening clamp is mounted in the connection seat.

According to the fastening clamp assembly described above, the connection seat has a pair of sides extending from both sides of the bottom, the pair of sides are disposed oppositely, and each of the pair of sides includes a sidewall and a convex edge, where the sidewall is connected to the bottom, the convex edge extends from the sidewall towards the other side of the pair of sides, and the side and the convex edge enclose to form a receiving slot in a pair of receiving slots.

According to the fastening clamp assembly described above, the connection seat is removably connected or integrally formed with the first component.

The fastening clamp in the present application can be connected to a cylindrical part of a vehicle.

Various specific embodiments of the present disclosure will be described below with reference to the attached drawings that form a part of this Specification. It should be understood that while terms denoting orientation, such as "front," "rear," "upper," "lower," "left," "right," etc., are used in the present application to describe various exemplary structural parts and elements of the present application, these terms are used herein for convenience of illustration only and are determined based on the exemplary orientations shown in the attached drawings. Since the examples disclosed in the present application may be disposed in different orientations, these terms denoting orientation are for illustrative purposes only and should not be considered as limiting. The same or similar reference numerals used in the present application refer to the same components where possible.

<FIG> is a perspective view of a first example of a fastening clamp in the present application, <FIG> is a perspective view of the fastening clamp of <FIG> at a second angle, <FIG> is a top view of the fastening clamp of <FIG>, and <FIG> is a side view of the fastening clamp of <FIG>. <FIG> show a structure of the fastening clamp.

As shown in <FIG>, a fastening clamp <NUM> is used to connect a first component to a second component having a connecting post. The fastening clamp <NUM> includes a substrate <NUM> and a clamping portion <NUM>. The substrate <NUM> is generally flat and has a first side <NUM> and a second side <NUM>. The substrate <NUM> has a mounting hole <NUM> running through the first side <NUM> and the second side <NUM> of the substrate <NUM>. The mounting hole <NUM> has a centerline C that extends through the center of the mounting hole <NUM> and perpendicular to the plane in which the mounting hole <NUM> is located. The clamping portion <NUM> extends from the first side <NUM> in a direction away from the substrate <NUM>. The clamping portion <NUM> includes three first retaining legs <NUM>, <NUM>, and <NUM>, and three second retaining legs <NUM>, <NUM>, and <NUM>. The three first retaining legs <NUM>, <NUM>, and <NUM> and the three second retaining legs <NUM>, <NUM>, and <NUM> are staggered along a circumferential direction. The height of the three first retaining legs <NUM>, <NUM>, and <NUM> is greater than the height of the three second retaining legs <NUM>, <NUM>, and <NUM>, so that the top of the three first retaining legs <NUM>, <NUM>, and <NUM> is higher than the height of the three second retaining legs <NUM>, <NUM>, and <NUM>. The three first retaining legs <NUM>, <NUM>, and <NUM> and the three second retaining legs <NUM>, <NUM>, and <NUM> are all resilient to some extent and deflectable relative to the substrate <NUM>. In some examples of the present application, the three first retaining legs <NUM>, <NUM>, and <NUM> and the three second retaining legs <NUM>, <NUM>, and <NUM> are provided with a thinned or narrowed design at a connection to the substrate to adjust elasticity of the three first retaining legs <NUM>, <NUM>, and <NUM> and the three second retaining legs <NUM>, <NUM>, and <NUM> to a suitable range.

Each of the three first retaining legs <NUM>, <NUM>, and <NUM> includes a body portion <NUM> and an extension portion <NUM>, where the body portion <NUM> is located between the substrate <NUM> and the extension portion <NUM>, and the body portion <NUM> is inclined at a greater angle with respect to the substrate <NUM> than the extension portion <NUM>. Each of the first retaining legs <NUM>, <NUM>, and <NUM> generally presents a shape that curves toward the centerline C of the mounting hole <NUM>. The distal end of the extension portion <NUM> forms a contact <NUM> capable of contacting the connecting post of the second component. The contact <NUM> is arranged along the direction of a helix line, i.e., extends helically around the centerline of mounting hole <NUM>. Each contact <NUM> of the three first retaining legs <NUM>, <NUM> and <NUM> is arranged around the cylindrical connecting post of the second component. The height of the contact <NUM> is different on both sides in the circumferential direction, where the height on a first side is greater than the height on a second side. The first side of each contact <NUM> is located between second sides of two adjacent contacts <NUM>. That is, in the direction of rotation along the circumference, the first side of each contact <NUM> is located upstream or downstream of the second side.

The three second retaining legs <NUM>, <NUM>, and <NUM> extend from the substrate <NUM> towards the centerline C of the mounting hole. The distal end of each second retaining leg also has a contact <NUM>, and similar to the contact <NUM>, the contact <NUM> is capable of contacting the connecting post of the second component. The contact <NUM> is arranged along the direction of a helix line, i.e., extends helically around the centerline C of mounting hole <NUM>. Each contact <NUM> of the three first retaining legs <NUM>, <NUM> and <NUM> is arranged around the cylindrical connecting post of the second component. The height of the contact <NUM> is different on both sides in the circumferential direction, where the height on a first side is greater than the height on a second side. The first side of each contact <NUM> is located between second sides of two adjacent contacts <NUM>. That is, in the direction of rotation along the circumference, the first side of each contact <NUM> is located upstream or downstream of the second side. The contacts arranged along the direction of the helix line facilitate removal of the fastening clamp from the second component.

In one example of the present application, the distance from the contact <NUM> to the centerline C is equal to the distance from the contact <NUM> to the centerline C.

In another example of the present application, the contact <NUM> is farther from the centerline C than the contact <NUM> is from the centerline C.

In one example of the present application, the first retaining legs <NUM>, <NUM>, and <NUM> and the second retaining legs <NUM>, <NUM>, and <NUM> are all deformed after being mounted in place, and the contact <NUM> and the contact <NUM> are clamped with the connecting post of the second component at different heights of the connecting post of the second component, which can further strengthen the pulling force between the fastening clamp and the connecting post of the second component.

In another example of the present application, the first retaining legs <NUM>, <NUM> and <NUM> are deformed after being mounted in place, the contact <NUM> is clamped with the connecting post of the second component, a small amount of deformity or no deformation occurs at the contact <NUM>, and the contact <NUM> has a small amount of clearance abutting on the connecting post of the second component or with the connecting post of the second component. The second retaining legs <NUM>, <NUM>, and <NUM> are used to prevent the fastening clamp from tilting relative to the connecting post of the second component.

The substrate <NUM> has a front side <NUM> and a back side <NUM>, and a pair of convex portions <NUM> and <NUM> protruding from a second side <NUM> of the substrate <NUM>. The convex portions <NUM> and <NUM> form an anti-release structure to prevent the fastening clamp from falling off of the second component. The convex portions <NUM> and <NUM> are generally triangular, and the convex portions <NUM> and <NUM> taper and gradually become thicker in a direction from the front side <NUM> to the back side <NUM>. The convex portions <NUM> and <NUM> thus form a barb. The convex portions <NUM> and <NUM> have tips <NUM> and <NUM> proximate the back side <NUM>, and the tips <NUM> and <NUM> are capable of at least partially clamping into the connecting post of the second component to prevent the fastening clamp from falling off of the connecting post of the second component.

In the present application, the fastening clamp is an integral member made through metal sheet stamping, and has a certain hardness. In the present application, the substrate <NUM> has double layers and is formed by bending a metal sheet, thereby strengthening the strength of the substrate <NUM>.

<FIG> is a perspective view of a first example of a fastening clamp assembly in the present application, <FIG> is an exploded view of the fastening clamp assembly of <FIG>, and <FIG> is a cross-sectional view of the fastening clamp assembly in the present application.

As shown in <FIG>, the fastening clamp assembly <NUM> includes a connection seat <NUM> and a fastening clamp <NUM>, the fastening clamp <NUM> is mounted in the connection seat <NUM>, and the connection seat <NUM> is used for connecting to the first component. The connection seat <NUM> includes a head <NUM>, a neck <NUM>, and a body <NUM>, both of the head <NUM> and the neck <NUM> are cylindrical, and the diameter of the head <NUM> is larger than the diameter of the neck <NUM>. The body <NUM> is generally a cube, and the body <NUM> includes a bottom <NUM>, a pair of sides <NUM> and <NUM>, and a top <NUM>. The top <NUM> is connected to the head <NUM>, and the top <NUM> is larger in size than the neck <NUM>. The sides <NUM> and <NUM> extend from both sides of the bottom <NUM> and connect to the top <NUM>. The sides <NUM> and <NUM>, the bottom <NUM>, and the top <NUM> enclose to form a cavity <NUM>, and the fastening clamp is able to enter the cavity <NUM>. The bottom <NUM> has an opening <NUM> in communication with the cavity <NUM>. The side <NUM> includes a sidewall <NUM> and a convex edge <NUM> extending from an inner side of the sidewall <NUM> toward the side <NUM>. The side <NUM> includes a sidewall <NUM> and a convex edge <NUM> extending from an inner side of the sidewall <NUM> toward the side <NUM>. A receiving slot <NUM> is formed among the convex edge <NUM>, the bottom <NUM>, and the sidewall <NUM>, and a receiving slot <NUM> is formed among the convex edge <NUM>, the bottom <NUM>, and the sidewall <NUM>.

The body <NUM> also includes a front end and a back end, the front end has an opening <NUM>, and the back end has a stop portion <NUM>. The stop portion <NUM> and the bottom <NUM> extend towards the top <NUM>. In one example of the present application, the stop portion <NUM> is flush with the top of the convex edges <NUM> and <NUM>. The substrate <NUM> is capable of being inserted into the receiving slots <NUM> and <NUM> in a direction from the front side <NUM> to the back side <NUM>. The receiving slots <NUM> and <NUM> can restrict movement of the fastening clamp <NUM> in the vertical direction. The convex portions <NUM> and <NUM> of the fastening clamp <NUM> can be clamped with the bottom <NUM> of the connection seat <NUM> to limit the fastening clamp <NUM> from sliding out of the connection seat in the direction from the back side <NUM> to the front side <NUM>. The stop portion <NUM> can restrict the fastening clamp <NUM> from sliding out of the connection seat in the direction from the front side <NUM> to the back side <NUM>. When the fastening clamp <NUM> is mounted in place in the connection seat <NUM>, the fastening clamp <NUM> can be stably located in the connection seat <NUM>. When the fastening clamp <NUM> is located in the connection seat <NUM>, the mounting hole <NUM> of the fastening clamp <NUM> is aligned with the opening <NUM> of the connection seat <NUM>.

In one example of the present application, the connection seat <NUM> is made of a plastic material having a hardness less than that of the fastening clamp <NUM>.

<FIG> is an exploded view of the fastening clamp assembly and the second component and the first component of the first example of <FIG>, <FIG> is a perspective view of the fastening clamp assembly after being connected to the second component and the first component, and <FIG> is a cross-sectional view of the fastening clamp assembly after being connected to the second component and the first component of <FIG>.

As shown in <FIG>, a fastening clamp assembly <NUM> is capable of connecting a second component <NUM> to a first component <NUM>. In one example of the present application, the second component <NUM> is a sheet metal of a vehicle body, the sheet metal has a sheet metal body and a cylinder <NUM> raised on the surface of the sheet metal body, and the first component is a pipe clamp for supporting a pipeline in a vehicle.

The first component has a pipe clamp connection portion <NUM> into which the fastening clamp assembly <NUM> can be loaded. The pipe clamp connection portion <NUM> includes a lower plate <NUM> having an opening <NUM> and an upper plate <NUM> having a slot <NUM>. When the fastening clamp assembly <NUM> is connected to the first component, the neck <NUM> of the connection seat <NUM> is able to enter the slot <NUM>, and the head <NUM> and the top of the body <NUM> are located on both sides of the upper plate <NUM>, respectively, so that the fastening clamp assembly <NUM> cannot move in the vertical direction relative to the first component. The shape of the pipe clamp connection portion <NUM> matches the shape of the connection seat <NUM>, so that the connection seat <NUM> cannot rotate relative to the first component <NUM>.

When the second component <NUM> is to be connected to the first component <NUM>, two connection operations may be employed as desired. The first operation first inserts the fastening clamp assembly <NUM> onto a cylindrical connecting post <NUM> of the second component <NUM> such that the cylindrical connecting post <NUM> passes through the opening <NUM> of the connection seat <NUM> and through the mounting hole <NUM> of the fastening clamp <NUM> in turn. When the fastening clamp assembly <NUM> is mounted in place, the top of the cylindrical connecting post <NUM> exceeds the distal ends of the three first retaining legs <NUM>, <NUM>, and <NUM>, and the fastening clamp assembly <NUM> is clamped on the cylindrical connecting post <NUM> via the elasticity of the first retaining legs <NUM>, <NUM>, and <NUM> and the second retaining legs <NUM>, <NUM>, and <NUM>. The first component <NUM> is then sleeved on the fastening clamp assembly <NUM> so that the first component <NUM> is connected to the connecting post <NUM> of the second component. The second operation first mounts the fastening clamp assembly <NUM> into the pipe clamp connection portion <NUM> of the first component <NUM>, and then inserts the first component <NUM> and the fastening clamp assembly <NUM> together onto the cylindrical connecting post <NUM> of the second component <NUM>.

In one example of the present application, when the fastening clamp <NUM> is connected to the cylindrical connecting post <NUM> of the second component <NUM>, the first retaining legs <NUM>, <NUM>, and <NUM> and the second retaining legs <NUM>, <NUM>, and <NUM> are deflected and clamped against the sidewall of the cylindrical connecting post <NUM>. The material hardness of the cylindrical connecting post <NUM> is lower than the material hardness of the contact of the first retaining legs and the second retaining legs, so that the contact can be partially inserted into the cylindrical connecting post <NUM> and the fastening clamp is stably clamped on the cylindrical connecting post <NUM>. When all the first retaining legs and the second retaining legs are tilted towards the cylindrical connecting post <NUM>, thereby applying an upward pulling force to the fastening clamp, the first retaining legs and the second retaining legs further clamp the cylindrical connecting post <NUM> such that the fastening clamp cannot be pulled out.

In another example of the present application, when the fastening clamp <NUM> is connected to the cylindrical connecting post <NUM> of the second component <NUM>, the first retaining legs <NUM>, <NUM> and <NUM> are deflected, clamped on the sidewall of the cylindrical connecting post <NUM>, and the second retaining legs <NUM>, <NUM> and <NUM> abut against or have a small gap with the cylindrical connecting post <NUM>. That is, the second retaining legs <NUM>, <NUM>, and <NUM> can prevent the fastening clamp <NUM> from tilting relative to the cylindrical connecting post <NUM> of the second component <NUM>; the first retaining legs <NUM>, <NUM>, and <NUM> clamp the cylindrical connecting post of the second component <NUM>, preventing the fastening clamp <NUM> from disengaging from the cylindrical connecting post <NUM> of the second component <NUM>.

<FIG> is an exploded view of a fastening clamp assembly of a second example of the present application and <FIG> is a perspective view of the fastening clamp assembly of the second example of <FIG> after being connected to a first component.

In the examples shown in <FIG>, the fastening clamp assembly includes a fastening clamp <NUM> and a first component <NUM>. The first component <NUM> is a pipe clamp. The fastening clamp <NUM> may be mounted directly on the first component <NUM> without the need of providing the connection seat <NUM>. The first component <NUM> is provided with receiving slots <NUM> and <NUM>, and the fastening clamp <NUM> is able to enter the receiving slots <NUM> and <NUM> and is not easily disengaged from the first component. The first component <NUM> and the fastening clamp <NUM> can be connected together to the second component having a cylindrical connecting post.

That is, in the second example of the fastening clamp assembly, it is equivalent to integrate the connection seat on the first component <NUM> without the need for separate arrangement of the connection seat.

<FIG> is a perspective view of a second example of a fastening clamp in the present application, and <FIG> is a perspective view of the fastening clamp of <FIG> at another angle. Similar to the fastening clamp of the first example shown in <FIG>, however, the structure of a substrate <NUM> of a fastening clamp <NUM> is different. As shown in <FIG>, the fastening clamp <NUM> includes the substrate <NUM> and a clamping portion <NUM>. The substrate <NUM> is generally flat and has a first side <NUM> and a second side <NUM>. The clamping portion <NUM> extends outwardly from the first side <NUM> of the substrate <NUM>. The substrate <NUM> also has a front side <NUM> and a back side <NUM>, and a front side flap <NUM> and a back side flap <NUM>. The back side flap <NUM> extends from the edge of the back side <NUM> in a direction away from the first side <NUM> of the substrate <NUM>, to form a stop portion <NUM>. That is, the extension direction of the back side flap <NUM> is substantially perpendicular to the extension direction of the substrate <NUM>. The back side flap <NUM> and the clamping portion <NUM> are located on both sides of the substrate <NUM>, respectively. The front side flap <NUM> is bent from the edge of the front side <NUM> towards the second side <NUM> of the substrate <NUM>, and the extension direction of the front side flap <NUM> is the same as the extension direction of the substrate <NUM>. In one example of the present application, the front side flap <NUM> fits the surface of the second side <NUM> of the substrate <NUM>.

The substrate <NUM> also has a stiffener <NUM> protruding from the surface of the first side <NUM> of the substrate <NUM>, the stiffener <NUM> is proximate to the back side <NUM> of the substrate <NUM>, and the stiffener <NUM> is an arc curved toward the centerline of the mounting hole <NUM> of the substrate <NUM>.

In this example, the stiffener <NUM>, the front side flap <NUM>, and the back side flap <NUM> all increase the strength of the fastening clamp <NUM> and prevent deformation of the fastening clamp <NUM>.

<FIG> is a perspective view of a third example of a fastening clamp assembly in the present application, and <FIG> is an exploded view of the fastening clamp assembly of <FIG>.

In the example shown in <FIG>, similar to the example shown in <FIG>, the fastening assembly includes a fastening clamp <NUM> and a first component <NUM>. The first component <NUM> is a pipe clamp. The first component <NUM> has a pipe clamp connection portion <NUM>. The pipe clamp connection portion <NUM> includes a pair of sidewalls <NUM> and <NUM>, a bottom <NUM>, and a pair of convex edges <NUM> and <NUM>. The pair of sidewalls <NUM> are connected to both sides of the bottom <NUM> and extend generally perpendicular to the bottom <NUM>. The pair of convex edges <NUM> and <NUM> extend from the inner side of the sidewalls <NUM> and <NUM> toward each other, respectively. The pair of sidewalls <NUM> and <NUM>, the bottom <NUM>, and the pair of convex edges <NUM> and <NUM> enclose to form a pair of receiving slots <NUM> and <NUM>, and both sides of the substrate <NUM> of the fastening clamp <NUM> are able to enter into the receiving slots <NUM> and <NUM>. The bottom <NUM> has a recess <NUM> whose shape mates with the shape of a stop portion <NUM> of the fastening clamp <NUM>. When the fastening clamp <NUM> is mounted in place in the first component <NUM>, the stop portion <NUM> enters the recess <NUM>. The stop portion <NUM> can restrict movement of the fastening clamp <NUM> relative to the first component <NUM> in the insertion direction of the fastening clamp <NUM>.

The fastening clamps <NUM> and <NUM> in the present application can be mounted on a cylindrical connecting post with a smooth outer wall. No threads or convex portions are required on the cylindrical connecting post. When a casting process is used for the vehicle body, the cylindrical connecting post may be integrally casted with the vehicle body, and they no longer need to be connected by welding or other joining processes.

Claim 1:
A fastening clamp, used for connecting a first component to a second component having a connecting post, comprising:
a substrate (<NUM>, <NUM>) on which a mounting hole (<NUM>) is provided, wherein the mounting hole (<NUM>) is used to receive the connecting post of the second component;
at least two first retaining legs (<NUM>, <NUM>, <NUM>), proximal ends of the at least two first retaining legs (<NUM>, <NUM>, <NUM>) connected to an edge of the mounting hole (<NUM>) and extending obliquely from one side of the substrate (<NUM>, <NUM>) towards one another in a direction away from the substrate (<NUM>, <NUM>), the at least two first retaining legs (<NUM>, <NUM>, <NUM>) being resilient and configured to deflect about the proximal ends of the at least two first retaining legs (<NUM>, <NUM>, <NUM>); and
at least two second retaining legs (<NUM>, <NUM>, <NUM>), proximal ends of the at least two second retaining legs (<NUM>, <NUM>, <NUM>) connected to the edge of the mounting hole (<NUM>) and extending obliquely from one side of the substrate (<NUM>, <NUM>) towards one another in a direction away from the substrate (<NUM>, <NUM>), the at least two first retaining legs (<NUM>, <NUM>, <NUM>) and the at least two second retaining legs (<NUM>, <NUM>, <NUM>) being on the same side of the substrate (<NUM>, <NUM>);
wherein distal ends of the at least two second retaining legs (<NUM>, <NUM>, <NUM>) are closer to the substrate (<NUM>, <NUM>) than distal ends of the two first retaining legs (<NUM>, <NUM>, <NUM>), and the at least two first retaining legs (<NUM>, <NUM>, <NUM>) and the at least two second retaining legs (<NUM>, <NUM>, <NUM>) are configured to be able to collectively retain the connecting post of the second component in the mounting hole (<NUM>),
characterised in that each of the at least two first retaining legs (<NUM>, <NUM>, <NUM>) comprise an extension portion (<NUM>) and a body portion (<NUM>) located between the substrate (<NUM>, <NUM>) and the extension portion (<NUM>), wherein the body portion (<NUM>) is inclined at a greater angle with respect to the substrate (<NUM>, <NUM>) than the extension portion (<NUM>) is inclined with respect to the substrate (<NUM>, <NUM>).