EP0506591B1 - Cover for an access or evacuation manhole - Google Patents

Abstract

The device comprises a frame (1) and a removable grating (2) which is hinged along an axis X-X of the frame, which grating consists of a series of bars connected in pairs, by at least one tie and running perpendicularly to the hinge axis X-X of the grating (2). The grating (2) furthermore comprises two intermediate bars (19A, 19B) connected to the other bars of the grating by their ends opposite the hinge axis X-X and the free ends of which interact, by elastic bending of the bars (19A, 19B) in the plane of the grating, with means (13, 14), arranged on the frame (1), for holding the grating (2) in the open and closed position. <IMAGE>

Description

The present invention relates to a device for crowning an access or exhaust chimney consisting of a removable tilting grid resting, when the device is in the closed position, in a frame sealed in the ground.

EP-A-0085306 thus discloses a grid pivotally mounted in its support frame and the locking of which, in the closed position, is obtained by means of a median bar whose end located at the opposite of the articulation axis comes, by elastic deformation, to snap under a stop of the frame.

However, such a crowning device has the drawback of not ensuring that the grid is kept in the open position.

EP-A-0280872 also discloses a grid articulated on its frame and at least one bar of which is provided, at its end opposite the articulation axis, with elastic fingers which, in the closed position of the grid, are housed under a projection of the frame. Here again, if such a device does indeed make it possible to lock the grid in the closed position, it does not however prevent inadvertent closing of the latter when it is in the open position.

On the other hand, there has been described in French patent application No. 89 12 938 (FR-A-2652606) filed on September 29, 1989 by the Applicant, a method and a device for crowning an evacuation chimney consisting of 'a grid articulated in a frame along a pivot axis of the grid corresponding to one side thereof, this grid being provided with bars connected to each other by spacers.

The grid is divided along its pivot axis into a middle part and two lateral parts connected elastically to the middle part, one end of the middle part adjoining the pivot axis being intended to bear against a corresponding surface of the frame by exerting a torque opposing the movement of the grid around its pivot axis.

An arrangement of the type described in the aforementioned patent makes it possible to ensure that the grid remains blocked to avoid accidental opening of the chimney and also to prevent acts of vandalism during which the grid can be voluntarily removed from its frame.

Furthermore, it maintains the grid in the open position.

The invention aims to further improve the technique described above by creating a crowning device in which on the one hand any accidental opening of the grid and on the other hand the untimely closing of the latter when it is in position open are avoided and this thanks to an elastic action of certain elements of the grid.

It therefore relates to a device for crowning an access or evacuation chimney comprising a frame and a removable grid articulated along an axis XX of the frame, consisting of a series of bars connected two by two, by at least a spacer and extending perpendicular to the axis of articulation XX of the grid, characterized in that the grid further comprises at least one intermediate bar connected to the other bars of the grid by its end opposite the axis of hinge XX and the free end of which cooperates by elastic bending of the intermediate bar in the plane of the grid with means projecting upwards to keep the grid in the open and closed position, provided on the frame, these means comprising chamfered and inclined surfaces which cooperate with inclined surfaces provided on said intermediate bar.

• la Fig.1 est une vue en plan d'un dispositif de couronnement de cheminée suivant l'invention;
• la Fig.2 est une coupe suivant la ligne 2-2 de la Fig.1;
• la Fig.3 est une vue de côté du dispositif de couronnement montrant la grille en position ouverte et en position fermée;
• la Fig.4 est une vue en plan de la grille du dispositif de couronnement suivant l'invention;
• la Fig.5 est une vue partielle en perspective du dispositif de couronnement suivant l'invention montrant les moyens de maintien de la grille en position ouverte ou fermée; et
• la Fig.6 est une vue partielle en perspective analogue à la Fig.5 montrant une variante des moyens de maintien de la grille.

The invention will be better understood with the aid of the description which follows, given solely by way of example and made with reference to the appended drawings, in which:

• Fig.1 is a plan view of a chimney crowning device according to the invention;
• Fig.2 is a section along line 2-2 of Fig.1;
• Fig.3 is a side view of the crowning device showing the grid in the open position and in the closed position;
• Fig.4 is a plan view of the grid of the crowning device according to the invention;
• Fig.5 is a partial perspective view of the crowning device according to the invention showing the means for holding the grid in the open or closed position; and
• Fig.6 is a partial perspective view similar to Fig.5 showing a variant of the grid holding means.

Referring first to Fig. 1 and 2, we see that the crowning device according to the invention comprises a frame 1 intended to be sealed in the ground, for example in a pavement, at the upper end of an evacuation or access chimney (not shown) and of a removable articulated grid 2 forming a cover .

The frame 1 has in plan a generally square or rertangular shape and has a vertical skirt 3, provided at its periphery with a peripheral support sole 4 serving to seal the frame and an inner flange 5 serving as a support surface for grid 2.

Two opposite sides 6, 7 of the skirt 3 each have in the immediate vicinity of a side 8 which is perpendicular to them, a cavity 9 of axis X-X parallel to the side 8, the two cavities 9 being coaxial.

The skirt 3 is terminated by a side 10 opposite and parallel to the side 8.

Each cavity 9 is formed in the skirt 3 of the frame 1 above the inner collar 5 approximately halfway between this collar and the top of the skirt 3.

The part of the collar 5 secured to the side 8 of the skirt 3 has, near its ends, two openings 11A, 11B defining between them an intermediate portion 12 each of whose two ends, parallel to the sides 6 and 7 of the skirt, has a chamfered surface 13 directed towards the inside of the frame and moving away from the opposite wall of the corresponding opening 11A, 11B.

Each end of the intermediate portion 12 of the collar delimited by the openings 11A, 11B, further supports a stop 14 projecting upwards from the frame 1 and integral with the side 8 of the skirt 3.

The arrangement of the chamfered surface 13 and the stop 14, is clearly seen in the perspective view of Fig.5.

Each stop 14 has in section the shape of a rectangular trapezoid. It is parallel to the sides 6 and 7 of the frame and consequently to the bars of the grid 2, and has on its side opposite the corresponding opening 11A, 11B, an inclined surface or ramp 15 ending in a horizontal apex 16.

The grid 2, of generally rectangular shape, is constituted by a series of parallel bars, each bar being connected to the neighboring bars by at least one spacer.

As can be clearly seen in FIG. 4, the grid comprises two external bars 17 each having near one of their ends, a pivot 18 intended to be housed in one of the cavities 9 of the frame 1, both pivots 18 being coaxial, of axis YY.

Two intermediate bars 19A, 19B which are connected by their ends opposite to the axis YY of articulation of the grid, on the one hand to the external bars 17 and on the other hand to bars 20 of a central part of the grid , by single spacers 21A, 21B, each have at its free end close to the axis YY, a vertical projection 22 directed downwards, the most inner longitudinal face, that is to say the one closest to the middle of grid 2 has an inclined surface or ramp 23, the inclination of this ramp being identical to that of the corresponding ramp 15 of the associated stop 14. The connecting bars 20 constituting the central part of the grid, complete the constitution thereof.

To mount the grid 2 in its frame 1, the latter being presented perpendicular to the plane of the frame, the grid is pinched at the free ends of the bars 17, this operation being made possible by the natural elasticity of the material constituting the grid 2 which is made for example in spheroidal graphite cast iron. The pivots 18 are thus placed opposite the cavities 9 of the frame 1 into which they penetrate when the clamping force is released.

Starting from the open position of the grid shown in phantom in Fig.3, to close the grid 2, we rotate it around its axis XX of rotation in the direction of arrow F and this, until the ramps 23 of the intermediate bars 19A, 19B come into contact with the chamfered surfaces 13 of the intermediate portion 12 of the collar 5.

When the ramps 23 come into contact with the chamfered surfaces 13, it is created between the flange 5 and the bars 19A, 19B, a couple opposing the continued rotation of the grid 2 thus preventing its untimely closing.

To overcome this torque, a downward force is applied to the grid 2, the intensity of which causes the ramps 23 to slide along the chamfered surfaces 13 of the intermediate part 12 of the flange 5. This sliding movement causes the elastic spacing of the bars 19A, 19B relative to their normal position, as shown in phantom in FIG. 1, so that the projection 22 of each of the bars 19A, 19B, can pivot around the axis XX thanks to the presence of the respective openings 11A, 11B formed in the flange 5 of the frame 1 which allow the corresponding projections 22 to pass.

The spacing of the bars 19A, 19B takes place in the plane of the grid 2.

When the grid reaches the closed position, the inclined ramps 23 provided on the projections 22 of the bars 19A, 19B come, due to the elastic reconciliation of the intermediate bars 19A, 19B, in contact with the inclined ramps 15 of the stops 14 carried by the ends of the intermediate portion 12 of the collar 5 and thus create a torque which opposes the accidental opening of the grid 2.

It will be noted that the ends of the bars 17, 20 of the grid, other than the intermediate bars 19A and 19B, which are located near the axis XX of rotation of the grid, do not prevent the rotation of the latter. due to the fact that their end surface adjoining the axis XX has a cylindrical or spherical shape centered on the axis XX, and having a radius such that during the rotation of the grid, these ends never come into contact or with the skirt 3, nor with the flange 5 of the frame 1.

As regards the intermediate bars 19A, 19B, the presence of a projection 22 located at a distance from the axis XX greater than its radius, makes it necessary to provide in the flange 5 the openings 11A and 11B which avoid blocking of rotation by contact between the projections 22 and the flange 5 of the frame 1.

To open the gate 2, it is necessary to apply a lifting force of an intensity such that the torque it generates is greater than the resistant torque which results from the contact between the ramps 23 of the projections 22 of the intermediate bars 19A and 19B and ramps 15 of the stops 14 integral with the frame 1.

The lifting movement of the grid 2 causes the inclined surfaces 23 to slide on the ramps 15 of the stops 14 and therefore, a lateral elastic spacing of the bars 19A, 19B relative to their rest position.

To ensure this movement, a bar forming a lever is generally used.

The spacing by elastic deformation of the intermediate bars 19A and 19B is ensured in the plane of the grid 2. Then, during the continuation of the rotation of the grid 2, the bars 19A and 19B see their respective protrusions 22 engaging in the respective openings 11A and 11B of the flange 5 thereby authorizing the continuation of the rotation of the grid 2 around the axis XX.

When the grid is brought into its open position, the projections 22 coming into contact with the chamfered surfaces 13 of the intermediate part 12, once again allow the bars 19A, 19B to be brought together by elastic return, in their rest position, to so that the grid is again blocked against any inadvertent closing movement.

The position of the stops 14 of the frame 1 between the intermediate bars 19A, 19B and the respective orientations of the ramps 15 of the stops 14 and 23 of the projections 22, ensure that the elastic bending of the bars is accompanied by a movement of separation of these bars.

One can also consider placing the stops integral with the frame 1 outside the intermediate bars and orienting the ramps of these stops and those of the ends of the intermediate bars so that during the rotation of the grid, the elastic bending of the bars in the plane of the grid is accompanied by a movement of approximation of the bars.

In the embodiment described with reference to Figs 1 to 5, the intermediate bars, which by elastic deformation in the plane of the grid, ensure the immobilization of the grid both in the open position and in the closed position , cooperating on the one hand with the ramps 15 of the stops 14 carried by the flange 5 and on the other hand, with the chamfered surfaces 13 of the intermediate part 12 of the flange, have projections 22 directed downwards which require provide in the collar 5 openings 11A, 11B for the passage of these projections during the rotation of the grid.

One can also imagine an embodiment in which the intermediate bars do not have a projection, but have ends of cylindrical or spherical shape, identical to those of other bars such as bars 17 and 20 of the grid.

Such a variant is partially shown in Fig. 6. We see in this figure, one of the intermediate bars 29B whose end 30 is cylindrical, of radius R such that when the grid to which the bar 29B belongs is mounted in frame 1, the axis of the surface cylindrical 30 is coincident with the axis XX of rotation of the grid.

Under these conditions, during the movement of the rotating grid, the surface of the end of the bar 29B will never come into contact with either the skirt 3 or the flange 5 of the frame 1.

In this embodiment, it is therefore not useful to provide openings to allow any part of the end of the bar 29B to pass during its rotational movement.

To block the grid in the open position and in the closed position, the frame 1 has stops 31 which extend over the entire width of the flange 5 parallel to the bars of the grid. Each of these stops 31 comprises a lateral ramp 32 intended to cooperate with an additional ramp 33 provided on each bar 29B in order to ensure its elastic spacing in the plane of the grid during the rotational movement of the latter and a chamfer end 34 allowing, by cooperation with the corresponding bar 29B, to let the said bar return to the rest position when the grid is in the open position in order to ensure that it is blocked against any untimely closing movement.

In the examples which have just been described with reference to the drawings, the grid of the crowning device comprises two intermediate bars ensuring, in cooperation with means provided on the frame, the maintenance of the grid in the open and closed position.

It will be understood that it is also possible that the grid has only one intermediate bar, preferably arranged in the central part of the grid and cooperating with corresponding holding means provided on the frame.

Claims (8)

1. Cover means for an access or drainage shaft comprising a frame (1) and a removable grid (2) hinged along an axis X-X on the frame, comprising a set of bars joined in pairs by at least one strut and extending perpendicularly to the hinge axis X-X of the grid (2), characterised in that the grid (2) also comprises at least one intermediate bar (19A, 19B; 29B) connected to the other bars of the grid by its end opposite the hinge axis X-X and whose free end acts together with upwardly projecting means (13, 14, 15; 31, 32, 34) holding the grid (2) in the open and closed positions, provided on the frame (1), through elastic bending of the intermediate bar (19A, 19B; 29B) in the plane of the grid, these means comprising chamfered sloping surfaces (13, 34; 15, 32) which act together with sloping surfaces (23, 33) provided on the said intermediate bar.
2. Cover means according to claim 1, characterised in that the grid comprises outer bars (17) which are provided with pivots (18) at the free ends thereof which engage through elastic bending of the outer bars (17) in corresponding cavities (9) in the frame (1), two intermediate bars (19A, 19B; 29B) each being connected to an outer bar (17) by a single strut (21A) and to a bar (20) of a central part of the grid through a single strut (21B).
3. Cover means according to either of claims 1 and 2, characterised in that each of the intermediate bars (19A, 19B) of the grid (2) has at its free end adjacent to the hinge axis of the grid in the frame (1) a downwardly pointing vertical projection (22) whose inner longitudinal face has a sloping or ramp surface (23) which acts together with a sloping surface (15) of a stop (14) which projects towards the top of the frame (1), fixed thereto and extending parallel to the bars of the grid (2), the said stops (14) forming the means for holding the grid (2) in the closed position by acting together with the projections (22) on the intermediate bars.
4. Cover means according to claim 3, in which the frame (1) is provided with an inner supporting collar (5) for the grid (2) in the closed position, characterised in that the openings (11A, 11B) for passage of the projections (22) from the intermediate bars (19A, 19B) when the grid rotates are fitted in the inner collar (5) of the frame (1).
5. Cover means according to claim 4, characterised in that the means for holding the grid (2) in the open position comprise bevelled surfaces (13) sloping towards the interior of the frame (1), provided on one of the walls of the openings (11A, 11B) which bound an intermediate portion (12) of the collar (5) and standing away from the other walls respectively of the corresponding openings.
6. Cover means according to claim 5, characterised in that the stops (14) acting together with the projections (22) are located along the walls of the openings (11A, 11B) incorporating the said bevelled surfaces (13).
7. Cover means according to either of claims 1 and 2, characterised in that each of the intermediate bars (29B) of the grid (2) comprise a free end close to the hinge axis of the grid of the frame (1) in a manner appropriate to enable it to turn about the hinge axis without coming into contact with the frame (1) and in that stops (31) which are parallel to the bars of the grid, and are provided with sloping surfaces (32) acting together with corresponding sloping surfaces (33) of the intermediate bars (29B), forming the said means for holding the grid in the closed position, are provided on the frame (1).
8. Cover means according to claim 7, characterised in that each of the stops (31) forming the said means holding the grid in the closed position comprises a bevelled terminal surface (34) sloping towards the interior of the frame, the bevelled surfaces (34) forming the said means for holding the grid in the open position together with the ends of the corresponding intermediate bars (29B).

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