Connection assembly of a ground protection / support surface formed of mats

Abstract

The invention relates to an improved connection assembly for connecting multiple ground protection / support surface mats (1). At least two mats (1) can be connected to each over adjacent sides by at least one connection assembly (2) and then disconnected after use, the connection assembly (2) comprising an interconnecting element (3) and four reinforcement plates (4), and the interconnecting element (3) comprising a connecting shank (5) and two pins, at least one pin being implemented as a swivel pin (7). Where only one pin is implemented as a swivel pin (7), the other pin is implemented as a fixed pin (6). In the assembled position, one of the pins (6, 7) is inserted into the corresponding connection slot (Id) of one mat (1) and the other of the pins (6, 7) is inserted into the corresponding connection slot (Id) of the adjacent mat (1). The connecting shank (5) substantially engages the corresponding surface of the reinforcement plates (4) attached to the upper face (la) of the adjacent mats (1) and the pins (6, 7) substantially engage the corresponding surface of the reinforcement plates (4) attached to the lower face (lb) of the adjacent mats (1) in the closed position.

Description

[0001] CONNECTION ASSEMBLY OF A GROUND PROTECTION / SUPPORT SURFACE FORMED OF MATS

[0002] The invention relates to an improved ground protection / support surface formed of mats and a connection assembly for connecting multiple mats. Mats are typically used as load-bearing support surfaces for temporary roadways and / or work pad areas, as well as to cover the ground for outdoor events such as concerts, sporting events, or the like. Such mats are generally made of durable materials with an embossed surface to improve traction, with mats able to be connected and disconnected using the connection assembly. This makes it easy to install and remove the mat on the ground surface. When interconnected, the mats provide a stable support surface for moving vehicles, equipment and / or people, or a working surface that can withstand heavy loads.

[0003] The state of the art is known for support surface mats interconnected by connection assemblies. Thus, patent document WO2022 / 119453 presents a mat in which the interconnecting connection assemblies joining the mats together are made with ball joints, thus allowing a certain degree of free movement of each mat, which can to a certain extent prevent the mats from breaking under load.

[0004] There are known mats (Isotrack H) where the mats are connected to each other by metal connecting straps which can be bolted into integrated and fixed connection positions on any side of the mat. Each individual metal connecting strap should be fastened with two bolts during installation. Using this method of connection the metal connecting straps sit above the surface of the mats when they are installed, exposing them to potential damage, in particular potential damage from vehicles with steel track systems that are in contact with the mat surface when driving over the mat.

[0005] There is a need to design a support surface formed of mats with a connection system that is particularly suitable for heavier transport, i.e. that is able to withstand heavy loads, mainly in the axial direction, perpendicular to the mat, and where the mats and connection assemblies are designed to prevent as far as possible any damage to the connection assembly and / or breakage of the mats, while ensuring that mats can be easily and quickly assembled and disassembled, and where the connection assembly is efficient and easy to use.

[0006] This technical problem is solved by a mat and a connection assembly according to the invention.

[0007] The invention is described in detail below and shown in the figures which show:

[0008] Figure 1 shows an example of a work area or platform (support surface) made up of multiple mats interconnected by the connection assembly. Figure 2 shows an example of how two adjacent mats are connected by a connection assembly - top view.

[0009] Figure 3 shows an example of how two adjacent mats are connected by a connection assembly - underside view.

[0010] Figure 4 shows one example of a connection assembly.

[0011] Figure 5 shows another example of a connection assembly.

[0012] Figure 6 shows two different examples of a connection assembly reinforcement plate.

[0013] Figure 7 shows an example of how two adjacent mats are connected by a connection assembly - crosssection.

[0014] . According to the invention, the support surface formed of mats includes at least two mats 1, which are releasably connectable to each other via adjacent sides with at least one, preferably two connection assemblies 2.

[0015] Mats 1 are made of any rigid material, preferably a thermoplastic polymer material, and may be rectangular, square, hexagonal or any other shape that when connected on adjacent sides allows the required ground surface area to be covered and the connection assembly 2 capable of being disconnected.

[0016] The connection assembly 2 comprises an interconnecting element 3 and four reinforcement plates 4, preferably of metal, which are fixed in dedicated and prefabricated sections on the mats 1. For this purpose, each of the mats 1 is on its upper face la and on its lower face lb provided with a dedicated section for dismantlable connection with the connection assembly 2, the dedicated section being realized as a recess lc continuing into the connection slot Id. In one embodiment mats 1 are provided with an additional reinforcement le around the recess lc on the upper and lower surfaces, in a form of a raised area above the face of the mat 1. The raised area le provides additional height difference in addition to the recess lc to further ensure that the interconnecting element 3 does not extend above the top face of the mat 1 when the mats 1 are assembled and is thus further protected against possible damage.

[0017] The pre-designed dedicated sections for connection are preferably located along the edges of the mats.

[0018] The reinforcement plate 4 is in the central part formed with a cut-out 4a with a width W and a length L, whereby when the reinforcement plate 4 is attached to the mat 1, the cut-out 4a is located above the connection slot Id.

[0019] In one implementation example, the reinforcement plate 4 is made as a flat plate and is fixed in the recess lc in the mat 1. In the second implementation example, the reinforcement plate 4 is made with a relief to at least fit into the recess lc in the mat 1, thereby further preventing direct loads on the mats 1 in due to the recess lc the reduced thickness of mat 1. Preferably, the reinforcement plate 4 conforms to the recess lc and the additional reinforcement le and is attached to the additional reinforcement le.

[0020] The first reinforcement plate 4 is thus fixed to the dedicated section on the upper face la of one mat 1 at the edge of the side which meets the adjacent mat 1 to which it can be connected and disconnected, and the second reinforcement plate 4 is fixed to the dedicated section on the lower face lb of that mat 1 at the same edge of that side; a third reinforcement plate 4 is fixed to the dedicated section on the upper face la of the second mat 1 at the edge of the side in contact with the first mat 1 to which it can be connected or disconnected, and a fourth reinforcement plate 4 is fixed to the dedicated section on the lower face lb of the second mat 1 at the same edge of the latter side.

[0021] Therefore, in the area of the recesses lc, a connection slot Id through the mat 1 is formed substantially at the cut-outs 4a of the corresponding reinforcement plates 4 when they are attached to the mat 1.

[0022] Preferably, the reinforcement plates 4 are screwed into the dedicated sections in mats 1; in this case, the reinforcement plates 4 contain through-holes 4b for screws or other fastening elements.

[0023] Interconnecting element 3 comprises: connecting shank 5 and two pins, with one pin being located at one end of the connecting shank 5 and the other pin being located at the other end of the connecting shank 5, where at least one pin is implemented as a swivel pin 7.

[0024] Where only one pin is implemented as a swivel pin 7, the other pin is implemented as a fixed pin 6.

[0025] The fixed pin 6 is fixed to the connecting shank 5 so that the longitudinal axis A2 of the fixed pin 6 is located at a distance R below the plane in which the connecting shank 5 extends, and the longitudinal axis A2 of the fixed pin 6 is substantially transverse to the longitudinal axis Al of the connecting shank 5.

[0026] Preferably, the connecting shank 5 and the fixed pin 6 are made in one piece, so that there is an intermediate section 5a between the connecting shank 5 and the fixed pin 6. The desired distance R between the fixed pin 6 and the connecting shank 5 is achieved by adjusting the angle of the intermediate section 5a. The angle of inclination a of the intermediate section 5a relative to the surface of the mat 1 is between 60 and 80 degrees, preferably an angle of inclination a of 65 degrees. Additionally, the angle of inclination a facilitates the insertion of the fixed pin 6 through the connection slot Id when connecting adjacent mats 1.

[0027] The swivel pin 7 is rotatably fixed to the connecting shank 5 so that the longitudinal axis A3 of the swivel pin 7 is located at a distance R below the plane in which the connecting shank 5 extends, and the longitudinal axis A3 of the swivel pin 7 in the closed position is substantially transverse to the longitudinal axis Al of the connecting shank 5, and in the open position, substantially parallel to the longitudinal axis Al of the connecting shank 5.

[0028] The swivel pin 7 is in the swivel axis A4 fixedly connected to the head 7a located above the connecting shank 5, so that by rotating the head 7a the swivel pin 7 is rotated from the open position to the closed position and vice versa. The distance R between the swivel pin 7 and the connecting shank 5 is achieved by means of a spacer 7b, preferably cylindrical, which is fixedly connected to the swivel pin 7. In one implementation example, the spacer 7b and the swivel pin 7 are made of one piece.

[0029] The spacer 7b is used to achieve the desired distance R between swivel pin 7 and connecting shank 5, while at the same time the spacer 7b serves the purpose of limiting the movement of connecting shank 5 in direction Al.

[0030] In one implementation example, such a rotatable attachment is achieved by a shaft with a head 7a through the hole 7c made in the connecting shank 5, with the head 7a being fixedly attached to the shaft on one side so that the head 7a is located above the hole 7c in the connecting shank 5, the spacer 7b is fixedly attached to the shaft below the hole 7c in the connecting shank 5 and a swivel pin 7 is fixedly attached to the spacer 7b on the opposite side, so that rotation of the head 7a results in rotation of the swivel pin 7 from the open position to the closed position and vice versa.

[0031] In one implementation example, which is preferred, the head 7a is designed in such a way as to extend above the upper surface of the connecting shank 5, and in another implementation example the top surface of the head 7a is aligned with the upper surface of the connecting shank 5, in which case the through-hole 7c is in the upper part of the connecting shank 5 formed with an enlarged recess into which the head 7a sinks.

[0032] Optionally, there is a visual marking on the upper (visible) surface of the connecting shank 5 and / or on the head 7a showing whether the swivel pin 7 is in the open or closed position.

[0033] Optionally, an additional spacer component (not shown) is inserted around the outer vertical wall of spacer 7b to allow rotation of spacer 7b therein, and is designed to reduce free play between the inner wall of the connection slot Id in mat 1 and the outer vertical wall of spacer 7b in the installed position, thereby reinforcing the connection and reducing movement between interconnecting element 3 and mat 1 at the location of swivel pin 7. The additional spacer component also stabilizes the position of the swivel pin 7 in the closed position and at the same time reduces any up-and-down movement of the swivel pin 7 in the closed position and prevents the mats 1 from moving in the direction Al.

[0034] In one implementation example, the interconnecting element 3 comprises a connecting shank 5 and two swivel pins 7, each of them being at one end of the connecting shank 5, and rotatably fixed to the connecting shank 5.

[0035] In another implementation example, the interconnecting element 3 comprises a connecting shank 5, a fixed pin 6 located at one end of the connecting shank 5 and a swivel pin 7 located at the opposite end of the connecting shank 5. The length L2 of the fixed pin 6 and the length L3 of the swivel pin 7 are individually greater than the width W of the cut-out 4a and smaller than the length L of the cut-out 4a of the reinforcement plate 4. The width W3 of the swivel pin 7 is smaller than the width W of the cutout 4a of the reinforcement plate 4, the width W2 of the fixed pin 6 is smaller than the width W of the cut-out 4a of the reinforcement plate 4.

[0036] Since the lengths of the pins 6 and 7 are greater than the width W of the cut-out 4a of the reinforcement plate 4, the axial forces on the mats 1 can be transferred to a larger area around the connection area, thus preventing any separation of the mats 1 at the connection points.

[0037] Since the lengths of pins 6 and 7 are greater than the width W of the cut-out 4a of the reinforcement plate 4, the loading of the mats 1 and of the connection assembly 2 prevents any disconnection, i.e. the possibility of a single pin 6 or 7 or both pins 6 and 7 slipping out of the connection slot Id.

[0038] Preferably, the length L2 of the fixed pin 6 is equal to the length L3 of the swivel pin 7 and the width W2 of the fixed pin 6 is equal to the width W3 of swivel pin 7.

[0039] The length of the connecting shank 5 is at least such that, when the mats 1 are connected, a certain spacing d between the mats 1 is enabled to ensure the necessary dilatation (the expansion and shrinkage) of mats due to temperature changes. Preferably, the spacing d between two adjacent mats 1 should be between 20-30 mm.

[0040] Optionally, the connecting shank 5 is designed with ribbed reinforcements 5b to limit or prevent possible twisting of the connecting shank 5, especially in the longitudinal direction.

[0041] Where the interconnecting element 3 comprises a connecting shank 5, a fixed pin 6 and a swivel pin 7, when connecting two adjacent mats 1 by a connection assembly 2, the reinforcement plates 4 are first fixedly attached in the dedicated sections on the mats 1, so that the cut-outs 4a are located substantially above the connection slots Id. Depending on the reinforcement plate 4 used, the reinforcement plate 4 is fixed either in the recesses lc or on the additional reinforcements le. The fixed pin 6 of the interconnecting element 3 is inserted through the connection slot Id of the first mat 1 so that the longitudinal axis A2 of the fixed pin 6 is substantially parallel to the longitudinal axis Al of the connecting shank 5, then the interconnecting element 3 is rotated through substantially 90 degrees so that the longitudinal axis A2 of the fixed pin 6 is substantially transverse to the longitudinal axis Al of the connecting shank 5. Then, the swivel pin 7 of the interconnecting element 3 is inserted through the connection hole Id of the second mat 1, so that the longitudinal axis A3 of the swivel pin 7 is substantially parallel to the longitudinal axis Al of the connecting shank 5, and with the head 7a, the swivel pin 7 is rotated by substantially 90 degrees, so that the longitudinal axis A3 of the swivel pin 7 is substantially transverse to the longitudinal axis Al of the connecting shank 5.

[0042] In the assembled position, the interconnecting element 3 is thus inserted with a fixed pin 6 into the connection slot Id of one mat 1 and with a swivel pin 7 into the connection slot Id of the adjacent mat 1.

[0043] Where the interconnecting element 3 comprises a connecting shank 5 and two swivel pins 7, when connecting two adjacent mats 1 by a connection assembly 2, the reinforcement plates 4 are first fixedly attached in the dedicated sections on the mats 1, so that cut-outs 4a are located substantially above the connection slots Id. Depending on the reinforcement plate 4 used, the reinforcement plate 4 is fixed either in the recesses lc or on the additional reinforcements le.The swivel pins 7 are inserted through the connection slots Id of the two adjacent mats 1 so that the longitudinal axes A3 of the swivel pins 7 are substantially parallel to the longitudinal axis Al of the connecting shank 5, and with the head 7a, the individual swivel pin 7 is rotated substantially 90 degrees so that the longitudinal axis A3 of each swivel pin 7 is substantially transverse to the longitudinal axis Al of the connecting shank 5. This implementation enables easier insertion of pins 7, as both pins 7 can be inserted simultaneously through the connection slots Id.

[0044] In the assembled position, the interconnecting element 3 is thus inserted with one swivel pin 7 into the connection slot Id of one mat 1 and with second swivel pin 7 into the connection slot Id of the adjacent mat 1.

[0045] It is desirable that the recesses lc in mats 1 in the vertical direction are at least the thickness of the pins 6, 7, to enable assembly and disassembly of the connection, i.e., joint. In the preferred implementation, the recess lc in the vertical direction is such that the connecting shank 5, the head 7a and the pins 6, 7 do not extend beyond the surface of the upper and lower faces of the mats 1 in the assembled position, which enables additional prevention of possible damage to the interconnecting element 3.

[0046] The connecting shank 5 substantially engages the corresponding surface of the reinforcement plate 4 fixed to the upper face la of the adjacent mat 1, and the fixed pin 6 and the swivel pin 7 , in the closed position, substantially engage the corresponding surface of the reinforcement plate 4 fixed to the lower face lb of the adjacent mat 1.

[0047] The vertical clearance of the connection - joint is adjusted by setting the distance R, the depth of recess lc and the height of relief le. It is desirable that the connection should have some clearance in the vertical direction to allow for flexing of mats 1 and up and down movement of the mats 1 during use, and to facilitate assembly and disassembly of the connection. Mats 1 can flex when heavy vehicles are driven on the mat, and the free movement of the connection prevents possible damage to the connection assembly 2. It is preferable that the joint clearance in the vertical direction is between 2 and 4 mm. The joint clearance in the vertical direction may be adjusted at least by setting the distance R and the depth of recess lc.

[0048] The above construction of the connection assembly 2 allows, among others, adjacent mats 1 to be interconnected, irrespective of which surface of the mat 1 is defined as the upper or driving surface.

Claims

Patent claims1. A connection assembly (2) of a ground protection / support surface formed of mats, wherein said surface is comprised of al least two mats (1), which are releasably connectable to each other via adjacent sides by at least one connection assembly (2) and each of the mats (1) is on its upper face (la) and on its lower face (lb) provided with a dedicated section for dismantlable connection with the connection assembly (2), said dedicated section being realized as a a recess (lc) extending into a connection slot (Id), characterized in that the connection assembly (2) comprises an interconnecting element (3) and four reinforcement plates (4), the reinforcement plates (4) being fixed in the dedicated sections provided on the upper face (la) and the lower face (lb) of each mat (1), wherein the interconnecting element (3) comprises a connecting shank (5) and two pins, with one pin being located at one end of the connecting shank (5) and other pin being located at the other end of the connecting shank (5), where at least one pin is implemented as a swivel pin (7), wherein the swivel pin (7) is rotatably attached to the connecting shank (5) so that a longitudinal axis (A3) of the swivel pin (7) is located at a distance (R) below a plane in which the connecting shank (5) extends and the longitudinal axis (A3) of the swivel pin (7) in a closed position is substantially transverse to a longitudinal axis (Al) of the connecting shank (5), and in an open position substantially parallel to the longitudinal axis (Al) of the connecting shank (5), and the swivel pin (7) is in a swivel axis (A4) fixedly connected to a head (7a) located above the connecting shank (5), so that by rotating the head (7a) the swivel pin (7) is rotated from the open position to the closed position and vice versa, and the distance (R) between the swivel pin (7) and the connecting shank (5) is defined by a spacer (7b), wherein the reinforcement plate (4) has a cut-out (4a) with a width (W) and a length (L), the cut-out (4a) being aligned above the connection slot (Id) when the reinforcement plate (4) is fixed in the dedicated section on the mat (1), wherein a length (L3) of the swivel pin (7) is greater than the width (W) of the cut-out (4a) and smaller than the length (L) of the cut-out (4a) of the reinforcement plate (4) and a width (W3) of the swivel pin (7) is smaller than the width (W) of the cut-out (4a) of the reinforcement plate (4), wherein in an assembled position, the connecting shank (5) substantially engages the corresponding surface of the reinforcement plates (4) fixed to the upper face (la) of the adjacent mats (1) and in theclosed position, the swivel pin (7) substantially engages the corresponding surface of the reinforcement plates (4) attached to the lower face (lb) of the adjacent mats (1).2.The connection assembly (2) according to claim 1, characterized in that one pin is implemented as a swivel pin (7) and the other pin is implemented as a fixed pin (6), the fixed pin (6) being fixed to the connecting shank (5) so that a longitudinal axis (A2) of the fixed pin (6) is located at a distance (R) below the plane in which the connecting shank (5) extends and the longitudinal axis (A2) of the fixed pin (6) is substantially transverse to the longitudinal axis (Al) of the connecting shank (5), a length (L2) of the fixed pin (6) is greater than the width (W) of the cut-out (4a) and smaller than the length (L) of the cut-out (4a) of the reinforcement plate (4), and a width (W2) of the fixed pin (6) is smaller than the width (W) of the cut-out (4a) of the reinforcement plate (4), wherein when assembled , the fixed pin (6) in the closed position substantially engages the corresponding surface of the reinforcement plates (4) attached to the lower face (lb) of the adjacent mats (1).

3. The connection assembly (2) according to claim 2, characterized in that the connecting shank (5) and the fixed pin (6) are made in one piece, so that between the connecting shank (5) and the fixed pin (6) there is an intermediate section (5a), wherein an angle of inclination (a) of the intermediate section (5a) with respect to the surface of the mat (1) is between 60 and 80 degrees, preferably the angle of inclination (a) of 65 degrees.

4. The connection assembly (2) according to the preceding claims, characterized in that the reinforcement plate (4) is made as a flat plate or the reinforcement plate (4) is implemented in relief to at least fit into the recess (lc) in the mat (1).

5. The connection assembly (2) according to the preceding claims, characterized in that the spacer (7b) is cylindrical and fixed to the swivel pin (7).

6. The connection assembly (2) according to the preceding claims, characterized in that the rotatable attachment is made by a shaft with a head (7a) through a through-hole (7c) made in the connecting shank (5), wherein the head (7a) being fixedly attached to the shaft on one side so that the head (7a) is located above the through-hole (7c) in the connecting shank (5), the spacer (7b) is fixedly attached to the shaft below the through-hole (7c) in the connecting shank (5) and a swivel pin (7) is fixedly attached to the spacer (7b) on the opposite side, so that rotation of the head (7a) results in rotation of the swivel pin (7) from the open position to the closed position and vice versa.

7. The connection assembly (2) according to the preceding claims, characterized in that the head (7a) is designed to extend above or to be aligned with the upper surface of the connecting shank (5), in which case the through-hole (7c) is in the upper part of the connecting shank (5) formed with an enlarged recess into which the head (7a) sinks.

8. The connection assembly (2) according to the preceding claims, characterized in that on an upper, visible, surface of the connecting shank (5) and / or on the head (7a) a visual marking is present, indicating whether the swivel pin (7) is in the open or closed position.

9. The connection assembly (2) according to any of the preceding claims, characterized in that an interface is provided around an outer vertical wall of the spacer (7b) to allow rotation of the spacer (7b) therein, and is designed to fill the space between an inner wall of the connection slot (Id) in the mat (1) and the outer vertical wall of the spacer (7b) when installed.

10. The connection assembly (2) according to the preceding claims, characterized in that a length of the connecting shank (5) is at least such that, when connecting the mats (1), a spacing (d) between the mats (1) is enabled to ensure necessary dilatation due to temperature changes, the spacing (d) between two adjacent mats (1) being between 20-30 mm.

11. The connection assembly (2) according to the preceding claims, characterized in that the recesses (lc) in the mats (1) in the vertical direction are at least the thickness of the pins (6, 7) to allow assembly and disassembly of a connection.

12. The connection assembly (2) according to any one of the preceding claims, characterized in that a connection clearance in the vertical direction is adjusted by at least defining the distance (R) and the depth of the recess (lc), wherein the connection clearance in the vertical direction is between 2 and 4 mm.

13. A ground protection / support surface made of mats (1), wherein said surface includes at least two mats (1) releasably connected to each other via adjacent sides with at least one connecting assembly (2) according to claims 1 to 12, , characterized in that the mats (1) are provided with an additional reinforcement (le) around the recesses (lc) made on the upper and lower faces,, said additional reinforcement (le) made as a relief raised above the surface of the mat (1) and, in the area of the recesses (lc) in the mat (1), a connection slot (Id) is made through the mat (1) substantially at the cut-outs (4a) of the associated reinforcement plates (4) when they are fixed to the mat (1).

14. A process of connecting the mats (1) into a ground protection / support surface by means of connection assemblies (2), characterized in that, when an interconnecting element (3) comprises a connecting shank (5), a fixed pin (6) and a swivel pin (7), when connecting two adjacent mats (1) with the connection assembly (2), the reinforcement plates (4) are first fixedly attached in dedicated sections on the mats (1), so that the cut-outs (4a) are located substantially above connection slots (Id); the fixed pin (6) of the interconnecting element (3) is inserted through the connection slot (Id) of the first mat (1) so that a longitudinal axis (A2) of the fixed pin (6) is substantially parallel to alongitudinal axis (Al) of the connecting shank (5), and the interconnecting element (3) is rotated through substantially 90 degrees so that the longitudinal axis (A2) of the fixed pin (6) is substantially transverse to the longitudinal axis (Al) of the connecting shank (5); the swivel pin (7) is then inserted through the connection slot (Id) of the second mat (1) so that a longitudinal axis (A3) of the swivel pin (7) is substantially parallel to the longitudinal axis (Al) of the connecting shank (5), and the swivel pin (7) is rotated through substantially 90 degrees by a head (7a), so that the longitudinal axis (A3) of the swivel pin (7) is substantially transverse to the longitudinal axis (Al) of the connecting shank(5), whereby in the assembled position the interconnecting element (3) is inserted with the fixed pin(6) into the connection slot (Id) of one mat (1) and with the swivel pin (7) into the connection slot (Id) of the adjacent mat (1).

15. A process of connecting the mats (1) into a ground protection / support surface by means of connection assemblies (2), characterized in that, when an interconnecting element (3) comprises a connecting shank (5) and two swivel pins (7), when connecting two adjacent mats (1) with the connection assembly (2), the reinforcement plates (4) are first fixedly attached in dedicated sections on the mats (1) so that the cut-outs (4a) are located substantially above connection slots (Id); the swivel pins (7) are inserted through the connection slots (Id) of the two adjacent mats (1) so that longitudinal axes (A3) of the swivel pins (7) are substantially parallel to a longitudinal axis (Al) of the connecting shank (5), and with a head (7a) each swivel pin (7) is rotated through substantially 90 degrees so that the longitudinal axis (A3) of each swivel pin (7) is substantially transverse to the longitudinal axis (Al) of the connecting shank (5), whereby in the assembled position the interconnecting element (3) is inserted with one swivel pin (7) into the connection slot (Id) of one mat (1) and with the other swivel pin (7) into the connection slot (Id) of the adjacent mat (1).

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