IE65927B1 - Means for securing a covering part to the frame of a road part - Google Patents

Abstract

Means intended for securing, in a removable manner, a generally polygon-shaped covering part (2), which may be a plane or concave grating or a covering plate, to a frame (1) interacting with the said part, these means comprising at least one elastic member (26) positioned in an open housing (25) arranged in the central region of one of the lateral faces of the frame, at least one fastening catch (11) integral with that lateral face of the frame which is opposite the one where the elastic member is located, a finger (30), integral with the covering part, the lower end of which has an enlargement (31) adapted to be snap-locked by interacting with the said fastening member, and a strip (32), integral with the part, which, in the position in which the said covering part is closed over the frame, interacts with the elastic member, the fastening catch (11) then being located in the position in which it is snap-locked with the finger (30) of the covering part. <IMAGE>

Description

This invention relates to roadway fittings such as grids or pavement cover plates, of the type comprising a removable cover which when in the closed position rests on a frame which is sealed into the ground or on a supporting structure. * 5 More particularly this invention relates to means for removably securing a cover part of the flat or concave grid type, a plate or other such of a generally polygonal shape to a frame which acts together with the said part. Preferably the cover part according to this invention has a generally triangular, square, 10 rectangular or trapezoidal shape in plan.

It is known that an attached mechanical part of the bolt, clamp, hook or similar type may be used to removably lock a grid or cover plate of a generally polygonal shape to a supporting frame.

Such locking devices nevertheless require the use of a special tool in order to release them and in some circumstances run the risk of becoming unlocked spontaneously as a result of the multiple vibrations caused by the passage of vehicles. Attached parts also have the danger that they may bind, thus becoming difficult to operate, or even jam, thus making unlocking impossible.

Devices where locking is achieved by trapping elastic fingers which are integral with the grip or plate in housings or beneath stops on the supporting frame are also known. Such arrangements, which are disclosed in particular by document GB-2 079 355 or BP0280 872 nevertheless make use of the elasticity of the material forming the grid or plate.

Another disadvantage of known locking systems lies in the fact that grids or plates rattle on their supports when rolling loads pass over them, thus constituting a permanent source of noise.

The purpose of this invention is therefore to overcame these disadvantages.

More particularly, this invention relates to a roadway fitting for this purpose comprising a rigid cover part of a generally polygonal shape, of the flat or concave grid or cover plate type, acting together with a frame through means which are designed to secure the cover part to the said frame in such a way that it can be moved upwards, these means comprising at least one elastic member positioned in a housing which opens towards the interior of the frame and is provided in the median region of one of the lateral faces of the frame, at least one hooking catch which is integral with the lateral inside face of the frame opposite that where the elastic member is located, a finger which is integral with the cover part, the lower end of which has a shoulder which makes a snap connection together with the said hooking catch, and a small bar which is directed downwards and is of one piece with the cover part, which bears against the inward face of the elastic member when the said cover part is placed in the frame, i.e. in the closed position, the hooking catch then being snapped into a position engaging the finger of the cover part.

These combined means thus offer safe locking which prevents the grid or plate being displaced from the frame when vehicles pass by, on account of its small weight, while at the same time eliminating the rattling noise which can be caused by the passage of rolling loads.

Other features and advantages will be apparent from the description which follows, which is given solely by way of a nonrestrictive example with reference to the appended drawings in whichs Figure 1 shows a view from above of an embodiment of a roadway fitting of the type comprising a cover part supported by a frame fitted with securing means according to the invention.

Figure 2 is a view of the frame together with the elastic member according to Figure 1 in cross-section along the line II—II, upon which is superimposed an end view of the cover part in accordance with the embodiment in Figure 1.

Figure 3 is a view from above of the frame according to the embodiment in Figure 1.

- Figure 4 is a view in cross-section along the line IV-IV in Figure 3.

Figure 5 is a view of the frame in accordance with Figure 3 in cross-section along the line V-V, together with the elastic member in accordance with the embodiment in Figure 1.

Figure 6 is a perspective view of the elastic member in accordance with the embodiment in Figure 1.

The roadway fitting illustrated in Figure 1 comprises a frame 1 and a removable cover part forming a lid. For reasons of convenience the cover part selected for this particular embodiment is a flat hinged grid 2. Frame 1 and grid 2 are both of a generally rectangular shape in plan.

Frame 1 (Figures 1 to 5) comprises a vertical skirt 3 which is provided around its perimeter with a bearing surface 4 which is designed to transmit the load and seal the frame into the ground or onto a supporting structure such as e.g. of concrete.

Two opposite lateral faces 5, 6 of skirt 3, parallel to an axis X-X located in the plane of frame 1, each have two wider portions 8A, 8B in skirt 3 facing the interior and the exterior of frame 1 respectively in the immediate proximity of the top of one lateral face 7 of skirt 3, perpendicular to faces 6, 7 and parallel to an axis Y-Y located in the plane of frame 1, outer enlargement 8B being longer than inner enlargement 8A.

In each of these enlarged portions 8A, 8B there is an opening 9A, 9B respectively, longitudinal to the Y-Y axis, opening 9B in enlarged portion 8B being longer than opening 9A in enlarged portion 8A.

These two openings 9A, 9B are opposite each other and as shown * in Figure 4 have a cross-section in the general shape of a triangle with rounded comers, thus producing a substantially oblong vertical portion in the vertical part thereof most within frame 1 and a substantially oblong horizontal portion in its lowest part.

Skirt 3 terminates in a lateral face 10 which is opposite and parallel to lateral face 7.

At its ends lateral face 10 incorporates two hooking catches 11 which project towards the interior of frame 1, which are incorporated with the internal face of the top of skirt 3 and which in cross-section, as shown in Figure 4, have a double cam comprising an upper ramp 11A which slopes downwards, i.e. towards the base of frame 1, and a lower ramp 11B which slopes upwards, i.e. towards the top of frame 1, the intersection between these two ramps 11A and 11B defining a ridge line 12 parallel to axis Y-Y.

Each of lateral faces 5, 6, 10 of skirt 3 has two supporting pads 13 in its median portion which project towards the interior of frame 1 and which have an upper bearing surface 14 parallel to the plane of frame 1.

Each of lateral sides 5, 6 of skirt 3 has two supporting pads with an upper bearing surface parallel to the plane of the frame, projecting towards the interior of frame 1, one of which 15 is located close to the extremity near to lateral face 10, and consequently close to hooking catches 11, and the other 16 is located in the opposite comer. • 35 Through an extension of their upper bearing surfaces, supporting pads 16 are incorporated into lateral face 7 of skirt 3, the upper face of their upper bearing surface parallel to the plane of the frame being located at a lower level than openings 9A, 9B as shown in Figure 5.

In its median portion, and preferably centred, lateral face 7 has a supporting pad 17 with an upper bearing member 18 whose upper bearing surface 18A and lower surface 18B are parallel to the plane of frame 1, as shown in Figure 5.

With reference to Figures 3 to 5, this upper bearing member 18 has a central recess 19, which opens towards the interior of the frame, of generally rectangular shape, thus dividing upper bearing member 18 into two protrusions 20A, 20B which are connected together by a longitudinal branch 21, parallel to axis Y-Y, and are of one piece with lateral face 7 of skirt 3.

Inner face 18B extends to the inner ends of protrusions 20A, 20B, parallel to lateral face 7, through a lip 22 which projects vertically towards the base of frame 1.

The median region of lateral face 7 extends towards the interior of frame 1 through a longitudinal projection 23, parallel to the plane of the frame, of a generally rectangular shape which is integral with the inner face of skirt 3 and coplanar with bearing surface 4 which, as shown in Figures 3 to 5, is positioned between protrusions 20A and 20B, i.e. below recess 19, the inner ends of frame 1 and parallel to face 7 of protrusions 20A, 20B and projection 23 being located in the same vertical plane.

The upper face of projection 23 is extended in the median region of its end furthermost within frame 1, and parallel to lateral face 7, by a lip 24 which projects vertically towards the top of frame 1, this lip 24 being preferably centred with respect to transverse ends 23A and 23B, parallel to axis X-X, and projection 23.

Lips 22 and 24 are such that the upper face of lip 24 is located at a lower level than the lower face of lip 22.

Lower face of supporting pad 17, whose protrusions 20A, 20B are provided with lips 22, and the upper face of projection 23 provided with lip 24 also define an open housing 25, together * with the inner wall of lateral face 7 of skirt 3, which is designed to receive and act together with an elastic member 26 which preferably comprises a piece of elastomer. In a variant embodiment according to the invention elastic member 26 comprises a spring.

With reference to Figure 6, this elastic member 26 has the general shape of a rectangular solid which has two upper notches 27A, 27B at its upper transverse ends designed to act together with protrusions 20A and 20B respectively, each equipped with their end lips 22, and also at the base of one longitudinal end a lower notch 27C which is designed to act together with lip 24 of projection 23. When elastic member 26 is positioned in housing 25 its lower surface rests partly on the upper surface of projection 23, and its upper surface is located in recess 19, at a level lying between lower face 18B and upper face 18A of upper bearing member 18. The vertical face of elastic member 26 opposite that where lower notch 27C Is located is then positioned with its top opposite longitudinal branch 21 of supporting pad 17. Owing to the special arrangement of lips 22 and 24 and the parts supporting the said lips, elastic member 26 is thus trapped in housing 25 in a perfectly stable way.

Supporting pads 13, 15, 16 and 17, which project towards the interior of frame 1, are such that the upper surfaces of their upper bearing members parallel to the plane of frame 1 are coplanar and thus form flat surfaces on which grid 2 is supported when in the closed position.

With reference to Figures 1 and 2, grid 2 comprises a set of bars 28 parallel to axis Y-Y, and connected together by at least two struts 29, parallel to axis X-X, two of struts 29 resting in the closed position with their ends on the upper flat bearing surfaces of supporting pads 13 and 17 of lateral faces 10 and 7 • of frame 1. Bars 28, which are regularly spaced and end in two end bars 28A, 28B, are positioned in such a way that the ends of » two of them rest on the flat upper bearing members of supporting pads 13 of lateral faces 5 and 6 of frame 1 in the closed position.

End bar 28A located next to lateral face 10 of frame 1 rests through its ends on the flat upper bearing members of supporting pads 15 of frame 1, in the closed position, each of its ends extending towards the outside of the grid, parallel to axis X-X, by means of a downwardly projecting finger 30 which is substantially perpendicular to the plane of the grid. With reference to Figure 2, the lower ends of fingers 30 end in a shoulder 31 incorporating a downwardly sloping ramp 31A directed towards the outside of grid 2 and a lower surface 3IB which is substantially parallel to the plane of grid 2, ramp 31A being connected to surface 31B through a substantially rounded surface 31C.

Ramps 31A on fingers 30, whose slopes correspond to those of ramps 11B of hooking catches 11, are located opposite hooking 25 catches 11 when in the closed position. End bar 28B, which is located alongside lateral face 7 of frame 1, rests through its ends on the flat upper bearing surface of supporting pads 16 of frame 1 when in the closed position and has a small bar 32 of generally rectangular shape, parallel to axis Y-Y, in its median 30 portion, and preferably centred, which projects downwards towards the base of grid 2, substantially perpendicular to the plane of the latter. When grid 2 rests on frame 1, this small bar 32 is tf positioned in a centred fashion opposite the longitudinal end of elastic member 26 furthest within frame 1, and its longitudinal ' 35 dimension is less than the distance separating the two protrusions 20A and 20B, and its lower face 32A is located above the upper surface of lip 24 of projection 23. The ends of bar 28B project parallel to axis X-X towards the exterior of grid 2, each of the two external faces of said bar 28B parallel to axis X-X incorporating a cylindrical pivot 33A, 33B respectively, projecting towards the exterior of the grid parallel to axis Y-Y.

These two pivots 33A and 33B are coaxial, and of different lengths, pivot 33A being shorter than pivot 33B, and when grid 2 is mounted on frame 1 are destined to be housed in openings 9A and 9B respectively provided in the respective widened portions 8A and 8B of frame 1, thus providing a hinge for grid 2 with respect to frame 1. The length of pivot 33B is such that when the latter fully penetrates opening 9B pivot 33A lies outside opening 9A and the diameter of these pivots 33A, 33B is such that they may undergo horizontal and vertical translational movements in the horizontal and vertical substantially oblong portions respectively of corresponding openings 9A and 9B which are intended to receive them.

As far as bar 28B is concerned (Figure 1), the end which is located close to lateral face 6 of frame 1 when grid 2 is in the closed position is also extended in its part furthest from lateral face 7 by a projection 34 directed towards the outside of grid 2, parallel to axis Y-Y, which in the closed position is located opposite the inner face of skirt 3, thus avoiding any possibility that pivot 33A may became accidentally dislodged. This projection 34 defines a free space 35 together with the outer cylindrical surface of pivot 33B, within which the upper wall of enlarged portion 8B, of thickness E, can lodge.

In order to fit grid 2 in a hinged maimer to frame 1, the latter is presented perpendicular to the plane of the frame and pivot 33B is placed deep in opening 9B, the latter being positioned in the upper part of the vertical oblong portion of opening 9B. Pivot 33A is then located opposite the upper part of the vertical oblong portion of opening 9A, i.e., with reference to Figure 4, opposite the left hand upper space of opening 9A, projection 34 being then located above enlarged portion 8B whose thickness E of the upper wall is lodged in the free space 35 between pivot 33B and projection 34. > Then, by maintaining grid 2 in a vertical position, the latter is moved horizontally in such a way as to bring pivot 33A into , 5 opening 9A, the outer face of projection 34, which is parallel to lateral face 6 of frame 1, being located in a substantially vertical plane adjacent to the plane containing the inner face of lateral face 6 of skirt 3. With grid 2 still in a perpendicular position to the plane of frame 1, this is then 10 moved downwards, pivots 33A and 33B then becoming positioned in the lower part of the vertical oblong portion of openings 9A and 9B respectively, and projection 34 becoming positioned opposite the upper wall of enlarged portion 8B through the intermediary of its outer face parallel to lateral face 6 of frame 1.

Grid 2 is thus in the open position, hinged with respect to frame I through pivots 33A and 33B which constitute its axis of rotation.

Locking of grid 2 onto its supporting frame consists of first lowering the latter from the open position by pivoting about its axis of rotation bringing rounded surface 31C of shoulder 31 of fingers 30 into contact with upper ramp 11A of hooking catches II of frame 1, small bar 32 being then opposite elastic member For this purpose, as a result of its rebated position in skirt 3 projection 34 guides grid 2 as it is positioned in the frame, in particular preventing any movement of the latter parallel to its hinge axis and at the same time through its centering effect holds small bar 32 opposite elastic member 26.

In a second stage, continuing the locking of grid 2, a downward thrust has to be applied to the latter, bar 32 then engages elastic member 26 and progressively compresses the latter in its housing 25, and this thrust has to be maintained until rounded surface 31C of shoulder 31 reaches and then crosses the ridge line 12 of hooking catches 11 by sliding along upper ramp 11A of hooking catches 11, this point corresponding to maximum compression of elastic member 26. During this compression stage t pivots 33A and 33B move towards the outside of the frame, by movement parallel to the frame of plane 1, along the ' substantially oblong horizontal portion of respective openings 9A and 9B.

Then, after ridge line 12 has been crossed, shoulder 31 slides along lower ramp 11B of hooking catches 11, through progressive decompression of elastic member 26, until ramp 31A of fingers 30 is in contact with said lower ramp 11B, thus achieving a position in which fingers 30 are snapped together with hooking catches 11, which corresponds to the final locked position. During this decompression stage pivots 33A and 33B move parallel to the plane of frame 1 in the opposite direction to that described in the previous compression stage. In the final locked position, i.e. when grid 2 is in the closed position, small bar 32 bears against elastic momha-r 26 and thus holds the latter under slight compression. This prestressing of elastic member 26 makes it possible to dampen and absorb any movement of grid 2 within the rebate of frame 1, particularly when rolling loads pass over it, and consequently avoids the rattling or chattering noise which can result.

In order to release grid 2 a bar merely has to be introduced between two adjacent bars 28 and a lever force exerted. Small bar 32 then compresses elastic member 26, thus allowing surface 31C of shoulder 31 to cross ridge line 12 of hooking catches 11, elastic member 26 then returning to its resting position, i.e. the uncompressed state. As will easily be understood, this release cannot occur accidentally.

As a variant, in order to make release of the grid even more difficult, securing ramps 11B and 31A which are designed to act together may be replaced by horizontal surfaces.

The embodiment which has just been described relates to a hinged grid, but it is nevertheless possible to envisage an arrangement in which a planar or concave grid, or a cover plate, rests on a supporting frame in a non-hinged manner. In this case pivots 33A, 33B may for example be replaced by a snap connection system of the type comprising fingers which are of one piece with the grid or plate, which acting together with hooking catches incorporated into the skirt of the frame is snapped together with at least one elastic member positioned in a housing in the said frame which is provided for the purpose, offering advantages which are identical to those mentioned above.

Claims (8)

1. A roadway fitting comprising a rigid cover part (2) of generally polygonal shape acting together with a frame (1) through the intermediary of means designed to fasten the said cover part (2) to the said frame (1) in an upwardly mobile manner characterised in that the said means comprise at least one elastic member (26) located in a housing (25) opening towards the interior of the frame and provided in the median region of one of the lateral faces of the frame, at least one hooking catch (11) which is integral with the inner lateral face of the frame (1) opposite that where the elastic member (26) is located, a finger (30) which is integral with the cover part (2), the lower end of which has a shoulder (31) which makes a snap connection with the said hooking catch (11), and a small bar (32), directed downwards and integral with the cover part (2), which when the said cover part (2) is placed in the frame (1), i.e. in the closed position, bears against the inwardly facing surface of the elastic member (26), the hooking catch (11) then being snapped into a position engaging the finger (30) of the cover part (2).

2. A roadway fitting according to claim 1, characterised in that the hooking catch (11) integral with the. inside face of the top of the skirt (3) of the frame (1) has a double cam comprising an upper ramp (11a), which slopes towards the base of the frame, and a lower ramp (lib), which slopes towards the top of the frame, the intersection between these two ramps defining a ridge line (12).

3. A roadway fitting according to claim 1, characterised in that the elastic member (26) is a piece of elastomer.

4. A roadway fitting according to claim 1, characterised in that the elastic member (26) is a spring.

5. A roadway fitting according to claim 1, characterised in that the shoulder (31) of the finger (30) comprises a ramp (31a), 13 which slopes downwards, towards the outside of the cover part (2), and a lower surface (31B) which is substantially parallel to the plane of the said cover part (2), the said sloping ramp being connected to the said lower surface through the intermediary of a substantially rounded surface (31C). 5 6. A roadway fitting according to claims 1, 2 and 5, characterised in that the slope of the ramp (31A) of the finger (30) corresponds to that of the ramp (11B) of the hooking catch 11.

6. 10

7. A roadway fitting according to claim 1, characterised in that the small bar (32) projects towards the base of the cover part (2), and is substantially perpendicular to the plane of the latter. 15

8. A roadway fitting according to claim 1, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.