LU100367B1

LU100367B1 - Adjustable support for a manhole cover

Info

Publication number: LU100367B1
Application number: LU100367A
Authority: LU
Inventors: Maxime Saunion; David Reignier
Original assignee: Redevo Ltd
Priority date: 2017-08-11
Filing date: 2017-08-11
Publication date: 2019-03-19
Also published as: WO2019030052A1

Abstract

Support (1) for a manhole cover comprising: an inner ring (4); an outer ring (2) arranged coaxially to the inner ring (4); wherein a first circumferential slanted portion (5) is provided in contact to or integral to the inner ring (4), a second circumferential slanted portion (3) is provided in contact to or integral to the outer ring (2), and wherein a circumferential pin (6.1, 6.2, 6.3) is provided between the two slanted portions (3, 5), the circumferential position of the pin (6.1, 6.2, 6.3) with respect to the slanted portions (3, 5) being adjustable to impact the axial position of the inner ring (4) with respect to the outer ring (2). The invention further relates to a tool and to a method for adjusting the relative axial position of the inner ring (4) with respect to the outer ring (2).

Description

ADJUSTABLE SUPPORT FOR A MANHOLE COVER

Description

Technical field [0001] The invention deals with a support for a manhole cover provided with means making it possible for the manhole cover to be flush with the road. The invention further relates to a tool and to a method for performing the adjustment of the position of the cover.

Prior art [0002] The document CA 2 892 191 A1 discloses a support for a manhole cover according to the preamble of claim 1. The support is made of two cylinders. The outer cylinder is fixed to the ground. The axial position of the inner cylinder can be adjusted with respect to the outer cylinder such that the manhole cover is flush with the road. To this end, the inner and the outer cylinders are provided with toothed racks that interacts with each other. This system has many drawbacks: the lengthy cylinders make it particularly cumbersome; the adjustment of the cover is not very precise and the whole weight that is applied on the support is only supported by a small surface.

[0003] The document US 2004/0109727 A1 discloses a tool in the form of a gantry to help adjusting the height of a manhole cover. To this end, appropriate sleeves are piled up onto each to form a support for the cover of appropriate height. In this example, to achieve a precise positioning of the cover, a large kit of sleeves is needed in such a way that a combination of the lengths of a plurality of sleeves fit the appropriate height needed for the support.

Summary of the invention

Technical problem [0004] The invention aims at providing a manhole cover support that is more compact and allows a more precise positioning of the manhole cover. The invention also provides solutions to the complexity of the adjustment of manhole cover in the prior art.

Solution [0005] This problem is solved by the support for a manhole cover according to claim 1.

[0006] According to a preferred embodiment, the support comprises: a plurality of slanted portions, evenly angularly distributed on the periphery of the rings, defining a plurality of pairs of slanted portions, and at least one crown bearing a set of pins, the set of pins being made of pins evenly angularly distributed on the periphery of the crown, such that one pin of the set of pins is interposed between the two slanted portions of each pair of slanted portions. By providing a set of pins, the weight distribution on the outer ring is better. Preferably, the system comprises more than one crown and there are therefore more than one pin intermediate the slanted portions. In a preferred embodiment, there are two or three crowns bearing each six pins. In other words, each of the six pairs of slanted portions are separated by two or three pins.

[0007] According to a preferred embodiment, the pins and/or the surface of the slanted portions is/are notched, corrugated, toothed or have a waved pattern. This ensure a better friction between the pins and the slanted portions to maintain the inner ring in position under more heavy loads than when the pins and slanted portions are flat surfaces.

[0008] According to a preferred embodiment, the second slanted portion provided on the outer ring is part of an annular element provided with teeth, notches or recesses, and in that the pins are provided with radial protrusions that slide in a groove of the outer ring on one side of the pin and in a groove of the annular element on the other side of the pin. This way, by rotating the annular element thanks to the teeth, notches or recesses, the pins and the second slanted portion are displaced angularly circumferentially and the inner ring moves axially upwards or downwards.

[0009] According to a preferred embodiment, the distance between the lowest position and the highest position of the inner ring is of about 40 mm and/or in the lowest position of the inner ring, the overall height of the support is of 70 mm. The overall height can alternatively be between 70 and 90 mm, for instance 80 mm. The distance between the highest and lower position of the inner ring is proportional to the overall height of the support in the lowest position. Preferably in the highest position of the inner ring, the overall height of the support is about 120 mm. In a preferred embodiment, the radius of the rings is between 60 and 100 cm, preferably about 80 cm. The pins can have a length of 100 to 200 mm, preferably 150 mm. Preferably, the length of the slanted portion is greater than the length of the pins. In particular, the length of each slanted portions can be between 200 and 210 mm.

[0010] The invention further relates to a manhole assembly comprising: a cover; a support for the cover; a hinge connecting the cover to the support; wherein the support is according to any of the embodiments disclosed above.

[0011] According to a preferred embodiment, the cover is provided with a central through hole. The central hole can allow to insert part of the tool to adjust the position of the inner ring as will be disclosed below. The central hole can be closed by a lid in normal condition when the cover is closed. The lid can be removed when an operation of adjustment is needed.

[0012] The problem stated above is also solved by the tool according to claim 8.

[0013] According to a preferred embodiment, the platform comprises a toothed portion, wherein a toothed plate is driven in rotation by the axle, and wherein a vertical rod fixed to the gantry holds at least one pinion, the pinion transmitting the rotation motion from the plate to the platform. This allows to divide the angular displacement of the pins compared to the displacement of the axle. Therefore, when the user rotates the central axle of a given angle, the pins are only displaced of a portion of this angle. This reduction allows an even more precise positioning of the height. In a particular embodiment, the ratio of reduction between the rotation of the axle and the angular displacement of the pins is comprised between 60 and 90%.

[0014] According to a preferred embodiment, the tool comprises three platforms, three pinions and three plates, the three pinions being of different diameters such that the actuation of the central axle generates a different angular displacement of the three crowns with pins. Preferably the lowest pinion is the smallest. The pinion arranged intermediate has a diameter which is two times the diameter of the lowest pinion and the uppermost pinion has a diameter which is triple the diameter of the lowest pinion. Of course, these ratios can vary. The number “three” for the platforms, pinions, plates and sets of pins allows to reach an advantageous ratio of elevation of the cover by angle of rotation of the axle. This number is however only an example and the number two, or a number above four is also adequate.

[0015] Preferably, the number of platforms is equal to the number of crowns of pins such that each set of pins is driven by a platform. Alternatively, a platform can drive more than one crown.

[0016] According to a preferred embodiment, the gantry is provided with a dial and/or a probe. This way, the position of the axle can be adjusted appropriately by rotating precisely the axle with respect to the indication on the dial. The indications on the dial are namely an image of the height of the support. A probe that is set according to the level of the road can also be provided to the gantry to help the user to adjust properly the position of the support.

[0017] According to a preferred embodiment, the tool comprises a central lever and an eccentric, such that a vertical motion of the axle and a rotative motion of the axle with respect to the gantry can be ensured by the sole action on the lever. This is particularly advantageous to simplify the actuation of the tool.

[0018] The problem stated above is also solved by the method according to claim 13.

[0019] According to a preferred embodiment, the step of adjusting the respective axial positions of the rings comprises the following steps: opening the cover; setting the platform and a secondary central axle; closing the cover; setting the lever, the central axle and the gantry; actuating the lever to rotate the axle until the desired height of the cover is reached; taking apart the lever, the central axle and the gantry; opening the cover; taking apart the platform and the secondary central axle; and closing the cover. Alternatively, the adjustment of the height of the inner ring can also be done when the cover of the manhole is open.

[0020] According to a preferred embodiment, the lever is actuated to lift all the pins such that the pins of different sets of pins do not contact each other and the pins do not contact the slanted portions; then the lever is actuated to rotate the central axle, in particular in accordance with an information displayed on the dial or the probe; and finally, the lever is actuated to put down in contact the pins and the slanted portions on each other.

Brief description of the figures [0021] The invention and its advantages will be more apparent with the exemplary embodiments of the accompanying figures, in which:

Figures 1A and 1B disclose the support for a manhole cover according to the invention in lowest and highest positions

Figures 2A and 2B disclose schematically the invention

Figure 3 discloses the outer ring of a first embodiment of the invention

Figure 4 shows an annular element of a first embodiment of the invention

Figure 5 represents an assembly of a first embodiment of the invention

Figure 6 shows a crown of pins in a second embodiment of the invention

Figures 7A and 7B represent the lowest and highest position of the support according to the second embodiment of the invention Figure 8 shows a tool according to the invention

Figures 9A and 9B show an assembly of a platform, pinion and plate for a support according to the second embodiment of the invention Figures 9C and 9D show two embodiments of a plate of the tool

Figures 10A and 10B show cross sections of the support according to the second embodiment of the invention with the tool according to the invention

Figure 11 represents a manhole cover with part of the tool in a third embodiment of the invention

Description d’un mode de réalisation [0022] Figure 1 illustrates a preferred embodiment of the manhole cover support 1 of the invention. The support 1 comprises an outer ring 2 which is fixed to the ground. The attachment to the ground can be effected by any regular means well known in the art, in particular screws that would be introduced through holes provided in a flange of the outer ring 2. The support 1 also comprises an inner ring 4. The cover of the manhole (shown only on figure 11 ) is attached to the inner ring 4, directly - that is, by means of a hinge (see 100.2 figure 11) - or indirectly through an intermediate part not shown. Figure 1A represents the lowest position of the support 1, wherein the inner ring 4 is encapsulated within the outer ring 2. Figure 1B shows the uppermost position of the support 1, wherein the inner ring 4 is protruding above the outer ring 2.

[0023] Figure 2 illustrates schematically the two positions in a projected view of the support 1. The inner ring 4 is provided with a slanted portion 5. The outer ring 2 is provided with a slanted portion 3. Each of the portions 3, 5 can be fixed and integral to the respective ring 2, 4. Alternatively, one or both of the slanted portions 3, 5 can be hold by an annular element adapted to be freely sliding in rotation on/below the outer/inner ring 2, 4 respectively as will be described further below. The two slanted portions’3, 5 are parallel to each other and describe a helix surface. In this particular example, three pins 6.1, 6.2, 6.3 are provided intermediate each pair of slanted portions 3, 5. Also, in this particular example, six pairs of slanted portions are foreseen, distributed angularly. The number of pairs of slanted portions 3, 5 and the number of pins 6 can however be chosen to be greater or smaller, depending on various factor and in particular the diameter of the rings or the weight of the vehicle that is expected on the road where the manhole is installed. Figure 2A discloses a lowest position of the inner ring 4 while figure 2B discloses the uppermost position of the inner ring 4.

[0024] Figure 3 shows the outer ring 2 of a first embodiment of the support 1 according to the invention. The outer ring 2 is provided with grooves 2.10, 2.11, 2.12. Only three pins 6.1, 6.2, 6.3 are represented, to increase the clarity of the drawing. The inner ring and the slanted portions are not shown. The pins 6.1, 6.2, 6.3 are provided with radial protrusions 6.11, 6.21, 6.31 on both their radially internal and external sides. The radial protrusion 6.11, 6.21, 6.31 on the radially external side of each pin engages a respective groove 2.10, 2.11, 2.12 of the outer ring 2. The radial protrusion 6.11, 6.21, 6.31 on the radially internal side of each pins 6.1, 6.2, 6.3 engages grooves of an annular element (see figure 4). As can be seen on figure 3, the radial protrusions 6.11, 6.21, 6.31 are not positioned at the same place for each of the pins 6.1, 6.2, 6.3. The lowest pin 6.1 has a protrusion 6.11 close to one of its end while the upper pin 6.3 has a protrusion 6.31 which is further away from the corresponding end. Also, the grooves 2.10, 2.11, 2.12 are not parallel to each other. This allows the pins 6.1,6.2, 6.3 to run an angular displacement that is different from each other. On figure 3, the positions of the pins 6.1, 6.2, 6.3 correspond to the lowest position of the inner ring (not shown). Figure 3 also shows a recess 2.2 which prevents the inner ring from rotating and a hole 2.3 for receiving a tool that will be described below.

[0025] Figure 4 shows an annular element 6. The annular element 6 is provided with grooves 8.1, 8.2, 8.3 for the internal protrusion 6.11, 6.21, 6.31 of the pins 6.1, 6.2, 6.3. This figure also shows the slanted portions 3 of the outer ring (not shown), which in this particular embodiment are borne by the annular element 8. The annular element 8 is also provided with recesses 8.4 that make it possible to interact with a tool to perform the rotation of the annular element 8 and to imply the vertical movement of the inner ring 4. Indeed, by rotating the annular element 8, the pins 6.1, 6.2, 6.3 are displaced angularly circumferentially and the inner ring 4 moves axially upwards or downwards.

[0026] Figure 5 shows the assembly of the inner ring 4, the annular element 8 and three pins 6.1, 6.2, 6.3 in this first embodiment. The annular element 8 is only partly shown, to let the pins 6.1, 6.2, 6.3 and the slanted surface 3, 5 visible. By rotating the annular element 8, the pins 6.1, 6.2, 6.3 follow a circumferential angular displacement. Due to the slanted portions 3, 5 of both the annular element 8 and the inner ring 4, the inner ring 4 moves up.

The inner ring 4 is also provided with a protrusion 4.2 that engages the recess 2.2 in the outer ring 2.

[0027] As a consequence, when the annular element 8 is rotated, the inner ring 4 only moves up or down but does not rotate. This is particularly advantageous to maintain the hinge (100.2 on figure 11) of the cover always in the direction of the movement of the vehicles on the road. Indeed, it is a standard safety requirement to provide the hinge upstream of the cover. In the event that the cover is not properly closed, a vehicle driving on the cover will not be damaged and will mainly tend to close the cover.

[0028] Figure 5 also shows the tool 10 that allows the user to easily rotate the annular element 8. This tool can be a simple handle with a pinion. The teeth of the pinion are such that they match the pitch of the recesses 8.4 in the annular element 8.

[0029] Figure 5 also shows the waved section of the pins 6.1, 6.2, 6.3 and of the slanted surfaces 3, 5. Indeed, the pins 6.1, 6.2, 6.3 and/or the slanted surfaces 3, 5 can be provided with a waved pattern, teeth or a zig-zag asymmetric pattern to increase the adherence and the stability of the support. Such pins surface can be adapted for any of the embodiments of the invention.

[0030] Figure 6 discloses the crown 12 bearing the pins 6.1 in a second embodiment of the invention. The pins 6.1 can be attached to the crown 12 by any conventional mean. Alternatively, the pins 6.1 can be integral to the crown 12. The preferred embodiment consists of 6 pins equally distributed in the periphery of the crown 12. Any other number or angular distribution is also an option.

[0031] Figures 7A and 7B represent a cross-section view of the second embodiment of the support (1). Figure 7A shows the lowest position of the inner ring 4, while figure 7B shows the uppermost position of the inner ring 4.

[0032] In this particular embodiment, there are provided two crowns 12, 14 of pins 6.1, 6.2 as shown on figure 7 and a third crown 16 bearing the slanted portions 5 of the inner ring 4, i.e. the first circumferential slanted portions 5. Alternatively, the slanted portions 5 can be integral to the inner ring 4.

[0033] In this example, the second slanted portions 3 are integral to the outer ring 2.

[0034] By rotating the crowns 12, 14, 16, the pins 6.1, 6.2 and the first slanted portions 5 are displaced angularly and the inner ring 4 moves axially. The inner ring 4 lays on the third crown 16. The third crown 16 rotates and moves axially upwards. A similar protrusion/recess arrangement 2.2, 4.2 as in the first embodiment are provided to ensure that the inner ring 4 only moves axially in translation and does not rotate.

[0035] The figure 8 illustrates a tool 20 according to the invention. The tool 20 aims at facilitating the rotation of the crowns 12, 14, 16 by the user, in a support 1 for a manhole cover according to the second embodiment. The tool 20 has a gantry 22. In this particular embodiment, the gantry 22 has three legs. The legs are aimed at being positioned on the ground around the manhole. The tool 20 has a central axle 24 positioned in the middle of the gantry 22. In use, the axle 24 is positioned in the central axis of the manhole and the rotation of the axle 24 generates a rotation of at least one platform 26, 28, 30. In the illustrated example, there are three platforms 26, 28, 30 to drive the three crowns 12, 14, 16 of the second embodiment of the support 1.

[0036] The tool 20 can has a lever 40 which is manipulated by the user. The lever 40 can pivot around a horizontal axis of the central axle. Thanks to an eccentric 42, the lever 40 can be pivoted such that an upwards translation of the central axle 24 is achieved. Since the central axle 24 is made of portions of different diameters (see figure 10), moving the axle 24 upwards makes the platforms 26, 28, 30 move upwards as well. The movement of the platforms 26, 28, 30 makes the crowns 12, 14, 16 move up as well.

[0037] The lever 40 can also make the axle 24 rotate around the vertical axis to make the platforms 26, 28, 30 rotate.

[0038] The gantry 22 can be provided with a dial 50 and/or a probe 52 to help the user set the appropriate axial displacement of the inner ring 4, or in other words the height of the cover of the manhole.

[0039] Above the platforms 26, 28, 30 can be positioned a plate 32 with radially external protrusions 32.1 which interact with recesses in the inner ring 4. This plate 32 which maintains the inner ring 4 in a fixed angular position is more detailed on figures 9C and 9D.

[0040] The platforms 26, 28, 30 can directly engage the axle 24. Alternatively, in a preferred embodiment, a reducer is provided between the axle 24 and the platforms 26, 28, 30. A vertical rod 34 is fixed to the gantry 22. The rod 34 bears three pinions (see figure 10) to reduce the ratio of rotation between the axle 24 and the platforms 26, 28, 30 such that the crowns 12, 14, 16 are rotated by different angles.

[0041] The axle drives three plates 25, 27, 29 in rotation. The periphery of the plates 25, 27, 29 is toothed. The rod 34 holds in position three pinions (visible on figure 10) that are interposed between the plates 25, 27, 29 and the platforms 26, 28, 30. This allows a precise positioning of the platform 26, 28, 30. For example, when the user moves the axle 24 (via the lever 40) of 20 degrees angle, the platforms 26, 28, 30 (and therefore the crowns 12, 14, 16) will only move of 12 to 18 degrees, and due to the angle of slanted portions 3, 5 which is preferably between 8 and 15 degrees angle, the cover will move upwards of about 9 to 25 mm when the diameter of the rings is about 60 cm. Therefore, a large movement of the user only implies a small adjustment for the height of the cover, rendering therefore the tool particularly precise.

[0042] Figure 9A illustrates the assembly of a platform 26, a plate 25 and a pinion 56. The platform 26 has a through hole 26.3 which receives the pinion 56. The radially external edge of the through hole 26.3 is toothed and cooperates with the pinion 56. The radially external edge of the plate 25 is also toothed and also cooperates with the pinion 56. Since the position of the pinion 56 is fixed in the rod (34 on figure 7 or 10), when the plate 25 is rotated, the platform 26 is also rotated, via the pinion 56. The plate 25 has notches at the central hole to interact with corresponding recess in the central axle 24, such that the rotation of the central axle 24 generates a rotation of the plate 25. In this example, the platform 26 freely rotates around the axle 24.

[0043] Figure 9B shows a plan view of the assembly of figure 9A. We can see that the pinion 56 is not purely cylindrical. It has two disc-shape portions above and below the toothed surface. The disc-shape portions extend radially beyond the toothed surface. This makes sure that when the platform 26, and the plate 25 moves upwards, the pinion 56 follows this movement.

[0044] The platform 26 is also provided with attachment means 26.1 to secure the platform 26 to the crown 12. The attachment means 26.1 are made of a pivoting tab that is easily manipulated by hand, i.e. without any tool.

[0045] Figure 9C shows a first embodiment of the plate 32. The plate has two radially external protrusions 32.1 which are axially inserted through recesses 4.3 of the inner ring 4 (see figure 9D). The plate 32 has a central hole 32.2 that receives the central axle 24 and an elongated slot 32.3 that receives the rod 34. In this first embodiment, the plate 32 is flat as can be seen on figure 9D. Alternatively, as is shown on figure 9E, the plate 32 can have a V-shape and can be provided with reinforcing ribs 32.4. This V-shape ensures that the weight of the inner ring 4 will be borne by the plate 32 and the protrusions 32.1 will not tend to exit the lower surface of the ring by radially internal deformation.

[0046] Figure 9F shows the plate 32 inserted below the inner ring 4. The arrows show how the protrusion 32.1 can penetrate the recess 4.3. When the plate 32 is moved up by the translation of the central axle 24, the ring 4 is then moved up as well.

[0047] In a preferred embodiment, the plate 32 is thicker than the platforms 26, 28, 30 because it is used to support more weight (the inner ring 4 and the cover) than the platforms (only supporting the crowns with the pins.

[0048] Figure 10 shows the tool in position in the manhole cover support according to the second embodiment of the invention. Figure 10A discloses a resting position wherein the tool is not engaged in the crowns of the support. Figure 10B shows a working position wherein the crowns 12, 14, 16 are lifted up and can therefore be rotated. This figure also shows in more details the axle 24 with the different diameters along its axle. By actuating the lever 40, the user will move up the axle 24 which will displace the respective platforms 26, 28, 30, plates 25, 27, 29, pinions 56, 58, 60 and crowns 12, 14, 16. This way, the pins 6.1, 6.2 and slanted portions 3, 5 are not anymore in contact one onto each other.

[0049] The displacement of the pinions 56, 58, 60 between figure 10A and 10B shows the way they can move along the rod 34. The pinions 56, 58, 60 can slide up and down along the rod 34 and can rotate around the longitudinal axis of the rod 34. The ratio of reduction between the axle 24 and the platforms 26, 28, 30 is between 60% and 90%.

[0050] The three pinions 56, 58, 60 have different diameters and therefore the ratio of reduction between the axle 24 and the platforms 26, 28, 30 is different for each platform.

[0051] The tool 20 functions as follows: the cover is opened, the platforms 26, 28, 30 are attached to the crowns 12, 14, 16. The central axle 24 is moved up by the actuation of the lever 40 and through the action of the eccentric 42. This makes the platforms 26, 28, 30 and the optional pinions 56, 58, 30 and plates 25, 27, 29 arrangement moves up. As a consequence, the pins 6.1, 6.2 and the slanted portions 3, 5 are not in contact with each other anymore. The central axle 24 is actuated in rotation by the lever 40, preferably until the mark on the dial 50 corresponding to the aimed level is reached. The platforms 26, 28, 30 rotate, preferably through the plates 25, 27, 29 and pinions 56, 58, 60 arrangements. This makes the crowns 12, 14 with pins 6.1, 6.2 and the crown 16 with the slanted portions 5 being angularly displaced. The lever 40 is actuated to move the central axle 24 downwards. The pins 6.1, 6.2 and slanted portions 3,5 lay then back onto each other. The platforms 26, 28, 30 are detached from the crowns 12, 14, 16 and finally the cover is closed.

[0052] The ratios of reduction mentioned above are such that that each of the crowns 12, 14, 16 have a very different movement, in angle as well as vertically. The ratios are such that if the pins are corrugated, they will match the corrugated pattern of each other when they fall down in contact to each other.

[0053] Figure 11 illustrates a third embodiment of the present invention, wherein the cover 100 is provided with a central hole 100.1 and the central axle 24 does not directly bear the platforms. On the contrary, the platforms are supported by a secondary central axle 54 that can be fixed to the (main) central axle 24. In practice, the length of the secondary central axle 54 is such that it does not protrude from the cover. The arrangement is such that the central axle 24 can be fixed to the secondary axle 54 through the central hole 100.1 of the cover 100. The connection is made by any suitable means, i.e. threaded extremity, bayonet connection, hexagonal section, etc. The cover 100 is connected to the inner ring 4 through a hinge 100.2 represented schematically on figure 11, and well known in the art.

[0054] We can see on figure 11 that the secondary axle 54 has different diameters to support the platforms 26, 28, 30.

[0055] In this third embodiment, the method to adjust the height of the cover 100 is as follows: the cover 100 is opened, the platforms 26, 28, 30 are positioned in contact with the crowns 12, 14, 16. The secondary central axle 54 is positioned together with the platform 26, 28, 30. Then the cover 100 is closed. To this end, the central hole 100.1 of the cover 100 and the height of the secondary central axle 54 are such that it is possible to close the cover 100 while the secondary central axle 54 is set in position within the manhole. Then, the (main) central axle 24 is connected to the secondary axle 54. The central axle 24 can be already mounted in the gantry 22. The central axle 24 is actuated in rotation, preferably until the mark on the dial 50 corresponding to the aimed level is reached. The central axle 24 and gantry 22 are then taken apart, the cover 100 is opened and the platform 26, 28, 30 and secondary central axle 54 are removed. Finally, the cover is closed 100. This method is particularly ergonomic for the user to adjust the height of the cover 100 while the cover 100 is closed. Alternatively or in combination to the dial 50, a probe 52 can be mounted on the gantry 22, set at the targeted height. When the cover 100 reaches the probe 52, the rotation of the axle 24 can be stopped.

[0056] When the optional pinions 56, 58, 60 are provided on the tool 20, the cover can have a second hole to receive the connection between the rod 34 and a secondary rod (not shown) that would bear the pinions 56, 58, 60 similarly to the arrangement of the central axle 24 and the secondary axle 54.

[0057] It has to be noted that the invention is only limited by the appended claims. In particular, the skilled person would depart from the specific embodiments that are only disclosed as illustration, through various adaptation, namely: the number of pins, crowns or slanted portions, the dimensions of any parts of the system, the direction of rotation to move up or down (clockwise/anticlockwise), the size or shape of the manhole (square, rectangle, oval, circular) and of the cover, and their application on the road (pathway, highway, parking, streets...).

[0058] The present invention has the further advantages that a precision of 1 mm can be reached, in a completely reversible way to re-adapt the height of the cover as often and as high or low as required. The tools and the design allow this adjustment to be made by one single man. The design is inexpensive and reliable since it employs cast iron.

Claims

1. Support (1) for a road plate cover (100) comprising: - an inner ring (4); an outer ring (2) disposed coaxially with the inner ring (4); characterized in that a first circumferential inclined portion (5) is provided in contact with or integrated with the inner ring (4), in that a second circumferential inclined portion (3) is provided in contact with or integrated with the outer ring ( 2), such that the first and second inclined portions (3, 5) define a pair of inclined portions substantially parallel to each other (3, 5), and in that at least one circumferential key (6.1, 6.2, 6.3) is provided between the two inclined portions (3, 5), the circumferential position of the key (6.1, 6.2, 6.3) relative to each of the inclined portions (3, 5) being adjustable.

2. Support according to claim 1, characterized in that it comprises: a plurality of inclined portions (3, 5), angularly equitably distributed over the periphery of the rings (2, 4), defining a plurality of pairs of inclined portions ( 3, 5), and at least one ring (12, 14, 16) bearing a set of keys (6.1, 6.2, 6.3), the key play (6.1, 6.2, 6.3) being made of keys (6.1, 6.2, 6.3) angularly equitably distributed around the periphery of the rings (12, 14, 16), so that a feather key (6.1, 6.2, 6.3) is interposed between two inclined portions (3, 5) of each pair inclined portions (3, 5).

3. Support according to claim 1 or 2, characterized in that the (the) key (s) (6.1, 6.2, 6.3) and / or the surface of the inclined portions (3, 5) is / are notched, corrugated, toothed or have a wave profile.

4. Support according to one of claims 1 to 3, characterized in that the second inclined portion (3) provided on the outer ring (2) is part of an annular element (8) provided with teeth, notches or housings ( 8.4), and in that the keys (6.1, 6.2, 6.3) are provided with radial protrusions (6.11, 6.21, 6.31) which slide in a groove (2.10, 2.11, 2.12) of the outer ring (2) of a side of the key (6.1, 6.2, 6.3) and in a groove (8.1, 8.2, 8.3) of the annular element (8) on the other side of the key (6.1, 6.2, 6.3).

5. Support according to one of claims 1 to 4, characterized in that the distance between the lowest position and the highest position of the inner ring (4) is about 40 mm and / or the overall height of the support is 70 mm.

6. Road plate comprising: - a cover (100); a support (1) for the cover (100); - a hinge (100.2) connecting the cover (100) to the support (1); characterized in that the support (1) is according to one of claims 1 to 5.

7. Road plate according to claim 6, characterized in that the cover (100) is provided with a central through hole (100.1).

8. Tool (20) for adjusting the axial position of the inner ring (4) relative to the outer ring (2) of the support (1) according to one of claims 1 to 5, the tool (20) comprising a gantry (22), a central shaft (24) adapted to be positioned vertically in the center of the gantry (22) and adapted to pivot about its vertical axis; and at least one platform (26, 28, 30) adapted to engage the key (6.1, 6.2, 6.3) or the ring gear (12, 14, 16) with the keys (6.1, 6.2, 6.3), the platform shape (26, 28, 30) being rotated about the vertical axis directly or indirectly by means of the central shaft (24).

Tool (20) according to claim 8, characterized in that the platform (26, 28, 30) comprises a toothed portion, in that a toothed plate (25, 27, 29) is rotated by the shaft (24), and that a vertical rod (34) which is fixed to the gantry (22) supports at least one pinion (56, 58, 60), the pinion (56, 58, 60) transmitting the rotational movement of the plate (25, 27, 29) to the platform (26, 28, 30).

10. Tool (20) according to one of claims 8 or 9, characterized in that it comprises three platforms (26, 28, 30), three pinions (56, 58, 60) and three plates (25, 27, 29), the three pinions (56, 58, 60) being of different diameters such that the activation of the central shaft (24) generates a different angular displacement of the three rings (12, 14, 16) with the keys (6.1.6.2, 6.3).

11. Tool (20) according to one of claims 8 to 10, characterized in that the gantry (22) is provided with a dial (50) and / or a probe (52).

12. Tool (20) according to one of claims 8 to 11, characterized in that it comprises a central lever (40) and an eccentric (42), so that a vertical movement of the shaft (24) ) and a rotational movement of the shaft (24) relative to the gantry (22) can be provided by the single action on the lever (40).

Method for adjusting the axial position of the inner ring (4) with respect to the outer ring (2) of a support (1) for a road plate cover (100) according to one of claims 1 to 5 , comprising a step of adjusting the relative axial position of the rings (2, 4) performed by a tool (20) according to one of claims 8 to 12.

14. The method of claim 13, characterized in that the step of adjusting the relative axial position of the rings (2, 4) comprises the following steps: - opening of the cover (100); - Placing platforms (26, 28, 30) and a secondary central shaft (54); closing the lid (100); - Implementation of the lever (40), the central shaft (24) and the gantry (22); - activating the lever (40) to turn the shaft (24) until the desired height of the lid (100) is reached; - Removal of the lever (40), the central shaft (24) and the gantry (22); opening the lid (100); - Removal of the platforms (26, 28, 30) and the secondary shaft (54); - closing the lid (100).

15. The method of claim 13 or 14, characterized in that the lever (40) is activated to lift the keys (6.1, 6.2, 6.3) so that the keys (6.1, 6.2, 6.3) of different sets of keys (6.1, 6.2, 6.3) are not in contact with each other and the keys (6.1, 6.2, 6.3) are not in contact with the inclined portions (3, 5); then the lever (40) is activated to turn the central shaft (24), in particular in accordance with information displayed on the dial (50) or the probe (52); and finally, the lever (40) is activated to lower in contact with each other the keys (6.1.6.2, 6.3) and the inclined portions (3, 5).