Device for assisting in the safe opening of a pivoting manhole cover

Abstract

The invention relates to an opening assistance device (10) for a pivoting manhole cover comprising a hollow body (11) extending longitudinally between the base and an open end, and a body (13) movable in longitudinal translation, a first end (131) of which is contained in the internal volume of the hollow body. The opening assistance device can take a so-called retracted position and a so-called deployed position. The device comprises an actuator (14) configured to generate a force which tends to bring the opening assistance device into the deployed position.The device further comprises a safety device (15) with two states, namely a locked state and an unlocked state, said safety device being configured to: when it is in the unlocked state, authorize the translation of the movable body (13) with respect to the hollow body, and when it is in the locked state, prohibit the translation of the movable body with respect to the hollow body, towards the retracted position of the opening assistance device, the safety device (15) being rigidly connected to the side wall of the hollow body (11). Figure for the abstract: figure 1.

Description

Title of the invention: Device for assisting in the safe opening of a pivoting manhole cover Technical field of the invention

[0001] The present invention relates to the technical field of devices for accessing underground networks.

[0002] The present invention relates in particular to a safety device capable of assisting a user in opening a cover of an underground network access device. For example, the underground network access device targeted within the scope of the present invention may be a manhole or a manhole. In this document, the terms “underground network access devices”, “manhole”, and “manhole” are synonymous.

[0003] The invention finds a particular, but not exclusive, application in devices for access to underground networks comprising at least one heavy cover, for example formed from a metal plate. Prior art

[0004] Devices for accessing underground networks conventionally comprise at least one cover, arranged so as to cover a roadway opening. Generally, these covers pivot around a frame positioned fixedly on the roadway opening. Such a cover allows, on the one hand, access to an underground network when it is pivoted into a so-called open position and, on the other hand, to close said roadway opening when it is pivoted into a so-called closed position.

[0005] However, these covers must withstand numerous constraints caused by the passage of successive loads ranging from a few tens of kilograms for a pedestrian traveling on a sidewalk-type roadway to several tons for a vehicle traveling on a roadway-type roadway.

[0006] This is one of the reasons why the covers of access devices to underground networks, in particular the covers commonly called "manhole covers", are generally formed from a resistant metallic material such as ductile iron.

[0007] However, these covers can be particularly heavy and therefore difficult to handle by a person wishing to access the underground network.

[0008] The weight of these covers can also pose safety issues. Once open, it is particularly important to avoid them closing accidentally while someone wants to access an underground network.

[0009] In this sense, existing devices for accessing underground networks generally include devices for assisting in opening covers and locking devices to ensure that the cover remains in the open position.

[0010] For example, document FR3029947A1 describes an access device comprising a cylinder for assisting in opening a cover and a locking device in the form of a holding leg, which makes it possible to hold the cover of the access device in position when it is fully open, and which thus makes it possible to secure it.

[0011] Although such access devices provide a solution to the problems mentioned above, they reduce the space available for accessing the underground installation because they require the use of several elements such as a support leg or a support intended to support this support leg (typically at the level of the frame to which the cover is articulated), which create obstacles in the opening of the access device.

[0012] Also, once the access device is closed, the retaining leg penetrates deep under the roadway. Consequently, these access devices cannot be used for all access device configurations, in particular when the available height under the cover is low or the retaining leg could interfere with elements present in the manhole, under the cover.

[0013] Furthermore, the use of such access devices requires the installation or formation of a support adapted to the movement of the holding leg on the cover and / or on the frame, which complicates the access device and increases its cost. Presentation of the invention

[0014] The present invention aims to resolve at least one of the problems mentioned above by proposing a suitable device for assisting in the opening of a pivoting manhole cover intended to equip access to an underground installation, such as a manhole or manhole.

[0015] By underground installation we mean, for example and in a non-exhaustive manner, a water drainage system located under a roadway, a buried electrical or telecommunications network, a water distribution network, a communications network (optical fiber for example), etc.

[0016] A pivoting manhole cover is rotatable between a so-called closed position and a so-called open position. The pivoting manhole cover is intended on the one hand to close access to an underground installation when it is positioned in the closed position and, on the other hand, to allow access when it is positioned in the open position.

[0017] The present invention thus relates to a device for assisting in opening a pivoting manhole cover intended to equip an underground installation, the opening aid device comprising: - a hollow body comprising a base, an open end and a side wall between said base and said open end, the hollow body delimiting an internal volume, the hollow body extending longitudinally between the base and the open end along a longitudinal axis called the main axis, the base comprising a first connecting interface, - a mobile body comprising a first end and a second end, the second end comprising a second connecting interface, at least the first end being contained in the internal volume of the hollow body, the mobile body being mobile in translation along the main axis.

[0018] Thus the opening assistance device can take, on the one hand, a so-called retracted position in which the distance between the first connecting interface and the second connecting interface is minimal and, on the other hand, a so-called deployed position where said distance between the first connecting interface and the second connecting interface is maximal.

[0019] The device further comprises: - an actuator configured to generate a force which tends to bring the opening assistance device into the deployed position, - a two-state security device, namely a locked state and an unlocked state, said security device being configured to: • when in the unlocked state, authorize the translation of the mobile body with respect to the hollow body, and • when in the locked state, prohibit the translation of the body movable relative to the hollow body towards the retracted position of the opening assistance device.

[0020] The safety device is rigidly connected to the side wall of the hollow body.

[0021] In the remainder of the description, the device for assisting in opening a lid of swivel gaze will also be referred to as “assistance device”.

[0022] A pivoting manhole cover will also be referred to as a “cover”.

[0023] Since the safety device is linked to the opening assistance device, the functions of opening assistance and securing a cover in the open position are combined in a single device. It is thus not necessary to provide the access device equipped with the safety device according to the present invention with an additional securing means. This simplifies the access device. Furthermore, no securing device, such as a holding leg and its support, hinders access to the underground infrastructure located under the access device.

[0024] In a preferred embodiment of the aid device, the wall of the hollow body comprises a through-hole. The safety device comprises a support, fixed to the wall of the hollow body, and a cylinder, the cylinder being movable in translation relative to the support between: • a so-called entry position in which the cylinder is completely outside the internal volume delimited by the hollow body, and • a so-called extended position in which the cylinder extends through the orifice in the wall of the hollow body.

[0025] Also, the mobile body comprises at least one contact zone capable of ensuring support on the cylinder in the extended position, so that: • when the cylinder is in the entry position, the safety device is unlocked, and • when the cylinder is in the extended position, the safety device is locked.

[0026] The size of such a security device is small. In the unlocked state, the size of the security device can be reduced to the length of the cylinder alone.

[0027] Advantageously, this results in a safety device that is simple to manufacture and has a reduced production cost.

[0028] The safety device may be an indexing finger. The cylinder is preferably made of steel or stainless steel. Advantageously, this results in a robust locking of the assistance device.

[0029] In an exemplary embodiment of the assistance device, the at least one contact zone of the mobile body is formed by the first end of the mobile body.

[0030] Advantageously, this results in a reduction in the number of parts required to maintain the assistance device in the deployed position, a reduction in the manufacturing time of the assistance device and a reduction in its manufacturing cost.

[0031] In an exemplary embodiment of the assistance device, the movable body obstructs the orifice in the side wall of the hollow body when the assistance device is in the retracted position and releases the orifice in the wall of the hollow body when the assistance device is in the deployed position.

[0032] Advantageously, this results in increased control of the state of the safety device, the safety device only being able to be in the locked state when the assistance device is in the deployed position.

[0033] In a preferred embodiment of the assistance device, the actuator is a helical spring.

[0034] Advantageously, this results in good reliability and easy maintenance of the assistance device, compared to an assistance device comprising another type of actuator. Also, the dimensioning of an assistance device comprising such an actuator is simple, compared to another assistance device comprising another type of actuator. The device can therefore be easily adapted to different sizes of pivoting manhole covers, particularly according to their weight.

[0035] For example, another type of actuator is a hydraulic or pneumatic pressure device. The use of such an actuator, hydraulic, pneumatic or otherwise, is however not excluded within the scope of the present invention.

[0036] In another exemplary embodiment of the assistance device, the actuator is at least partly contained in the internal volume of the hollow body, the actuator extending between the base of the hollow body and a bearing surface of the mobile body.

[0037] Advantageously, this results in a reduction in the size of the assistance device, compared to an assistance device in which the actuator would be positioned outside the hollow body. Also, the actuator is at least partly protected from the environment external to the assistance device, by the hollow body. By external environment, we mean for example the environment of an underground installation.

[0038] In a first alternative embodiment of the aid device, the support surface of the mobile body is formed by the first end.

[0039] The first end of the mobile body also being contained in the internal volume of the mobile body, it results that the actuator is totally protected from the environment external to the assistance device, by the hollow body.

[0040] In a second alternative embodiment of the assistance device, the mobile body is configured so that the support surface of the mobile body is formed by the second end.

[0041] For example, the first end of the movable body comprises an opening allowing the passage of the actuator and the movable body is hollow between the first end and the second end, so as to allow the internal passage of the actuator to the second end. This results in the use of a longer actuator without having to increase the minimum distance between the first connecting interface and the second connecting interface.

[0042] In use, such an actuator being less stressed than a smaller actuator, this results in increased overall robustness of the assistance device and reduced fatigue of the actuator when the assistance device is in the retracted position.

[0043] In another exemplary embodiment of the assistance device, the safety device is configured to spontaneously switch to the locked state when the opening assistance device is in the deployed position.

[0044] Advantageously, this results in increased reliability in keeping a cover in the open position. Such a safety device also makes it possible to reduce the risk of mishandling by a user wishing to access an underground installation. Mishandling means, for example, and in a non-exhaustive manner, partial engagement or forgetting to engage the safety device.

[0045] The invention also relates to a device for accessing an underground installation comprising a cover, a frame, the cover being connected to the frame, and an assistance device as described above in which: • the cover pivots relative to the frame between a so-called open position and a so-called closed position, the cover being intended on the one hand to block access to an underground installation when it is positioned in the closed position and, on the other hand, to allow access when it is positioned in the open position, • the cover comprises a first connecting element capable of ensuring a pivot connection with one of the two connecting interfaces among the second connecting interface of the second end of the mobile body of the aid device and the first connecting interface of the base of the hollow body of the aid device, • the frame forms an opening for access to an underground installation, the frame comprises a second connecting element capable of ensuring a pivot connection with the other of the two aforementioned connecting interfaces.

[0046] Unlike commercially available aid devices, the invention presented here has a reduced footprint, including at the level of the device for securing the aid device once the aid device is retracted. Also, the aid device does not penetrate deeply into the opening when the cover is closed.

[0047] As an exemplary embodiment of the access device, the latter is configured so that when the cover is in the closed position, the opening assistance device is in the retracted position, and when the cover is in the open position, the opening assistance device is in the deployed position.

[0048] Advantageously, the dimensioning of the stroke of the assistance device between its retracted position and its deployed position is proportional to the movement of the cover between its closed position and its open position. Since this movement of the cover can be measured in a simple manner, this results in easier dimensioning of the opening assistance device.

[0049] Also, the access device is configured such that the retracted position of the opening aid device is obtained when the cover is in the closed position, and the deployed position of the opening aid device is obtained when the cover is in the open position.

[0050] Furthermore, since the locking device of the assistance device is configured to spontaneously switch to the locked state when the opening assistance device is in the deployed position, the result is that the locking device can only be in the unlocked state as long as the cover is not in the open position. Thus, the invention cannot prevent a user from opening a closed cover.

[0051] In another exemplary embodiment, the access device comprises several covers and a single frame, each cover being associated with an opening assistance device.

[0052] Thus, the opening assistance device associated with each cover can be positioned close to an edge of the access opening to an underground installation. Advantageously, such an invention is more easily accessible to a user wishing to access an underground installation, in particular when the width of the access is significant, the user not having to lean over the opening to unlock the device.

[0053] Also, between two neighboring covers a so-called junction zone is formed. The present invention thus proves to be particularly advantageous in the absence of intermediate crosspieces at the frame level and under said junction zones. Unlike commercially available assistance devices, this results in a greater available access space due to the absence of obstacles formed by frame crosspieces. Brief description of the figures

[0054] The invention will be better understood on reading the following description, given by way of non-limiting example, and made with reference to the following figures:

[0055] [Fig.l] represents a side view in section of a device for assisting in opening a pivoting manhole cover, according to one embodiment of the invention;

[0056] [Fig.2] represents a top view of a device for assisting in opening a pivoting manhole cover, according to one embodiment of the invention;

[0057] [Fig. 3] represents a cross-section AA of a device for assisting in opening a cover in the retracted position (a) and in the deployed position (b), according to one embodiment of the invention;

[0058] [Fig.4] represents two three-dimensional schematic views of an area located around the safety device of the device for assisting in opening a pivoting manhole cover, when the safety device is in the locked position (a) or in the unlocked position (b), according to one embodiment of the invention;

[0059] [Fig.5] represents a side view of an access device to an underground installation, according to an embodiment where the access device comprises a cover;

[0060] [Fig.6] represents a side view of an access device to an underground installation, according to an embodiment where the access device comprises two covers.

[0061] In these figures, identical numerical references from one figure to another designate identical or analogous elements. Description of embodiments

[0062] An example of a device 10 for assisting in the secure opening of a pivoting manhole cover 20 in accordance with the present invention is now described and illustrated in FIGS. 1 to 6.

[0063] In the remainder of the description, the device for assisting in opening a pivoting manhole cover will also be referred to as the “assistance device”. The pivoting manhole cover will also be referred to as the “cover”.

[0064] [Fig.l] shows the aid device 10 in its entirety. The aid device 10 comprises: • a hollow body 11 comprising a base 111, an open end 112 and a side wall between said and said open end, the hollow body delimiting an internal volume 115, the hollow body extending longitudinally between the base 111 and the open end 112 along a longitudinal axis called the main axis 12, the base 111 comprising a first connecting interface 113, • and a movable body 13 comprising a first end 131 and a second end 132, the second end comprising a second connecting interface 133, at least the first end 131 being contained in the internal volume of the hollow body 11, the movable body being movable in translation along the main axis 12.

[0065] The movable body 13 is movable in translation between a first position and a second position. Preferably, the movable body 13 extends longitudinally between the first end and the second end along a longitudinal axis coaxial with the main axis 12. Advantageously, the first position of the movable body 13 corresponds to the retracted position of the assistance device 10 and the second position of the movable body 13 corresponds to the deployed position of the assistance device.

[0066] Preferably, the first connecting interface 113 and the second connecting interface 133 each comprise an orifice. The useful length of the assistance device corresponds to the distance formed between the center of the orifice of the first connecting interface 113 and the center of the orifice of the second connecting interface 133, along the main axis 12. In the retracted position, the distance between the center of the orifice of the first connecting interface 113 and the center of the orifice of the second connecting interface 133 is minimal. In the deployed position, this distance is maximal.

[0067] Preferably, the hollow body 11 is cylindrical in shape, with a constant section along the main axis 12, as illustrated in Figures 1 to 3. This advantageously results in easier manufacture of the hollow body.

[0068] The hollow body forms an internal volume 115 along the main axis 12, extending from the open end 112 to near the base 111. The base 111 does not, in the example shown, have an opening. In one embodiment of the invention, the base 111 is circular in shape.

[0069] The cross-section of the internal volume 115 is advantageously constant. By cross-section of the internal volume 115 is meant a section along a plane orthogonal to the main axis 12. The hollow body is thus easy to manufacture and allows optimal translational mobility of the mobile body 13 through the opening of the open end 112 and in the internal volume 115.

[0070] In another embodiment of the invention, the base 111 is of square or rectangular section. This advantageously results in the hollow body being manufactured from a bar of material of equivalent raw section.

[0071] The hollow body is made of a rigid material, offering resistance adapted to the constraints linked to the environment and the mechanical stresses to which it is subjected. By environment, we mean for example the environment of an underground installation. By mechanical stress, we mean for example a force resulting from a third element and transmitted through the aid device when this third element is in contact with the aid device.

[0072] In a preferred embodiment of the invention, the rigid material is a metallic material. For example, the rigid material is stainless steel or aluminum.

[0073] Preferably and as illustrated in Figures 1 to 3, the movable body 13 is of cylindrical shape, with an external section that is constant in shape and dimension along its longitudinal axis. As illustrated in [Fig.3], the external section of the movable body is of dimension substantially smaller than the section of the internal volume 115 of the hollow body so as to allow the insertion of at least the first end of the movable body into the internal volume 115 of the hollow body and reduce the clearance between the movable body and the internal volume of the hollow body. In other words, the movable body 13 has a cross-section that corresponds to that of the internal volume 115, apart from a functional clearance allowing the translation of the movable body 13 in the hollow body 11.

[0074] Advantageously, this results in improved translational mobility of the mobile body along the main axis 12.

[0075] In a preferred embodiment of the invention illustrated in [Fig. 3], the external section of the mobile body 13 is circular in shape. Advantageously, this results in optimal translational mobility of the mobile body along the longitudinal axis 12.

[0076] In the retracted position, the useful length of the assistance device 10 is minimal and the position of the movable body 13 in the internal volume 115 of the hollow body 11 is non-zero. More precisely, a space is formed between the base 111 of the hollow body 11 and the first end 131 of the movable body 13.

[0077] This space is called “free space” and is intended to accommodate at least part of the actuator 14 described below.

[0078] The assistance device 10 further comprises an actuator 14 configured to generate a force which tends to bring the assistance device into the deployed position. Preferably, the actuator 14 is at least partly positioned inside said free space. Advantageously, this results in protection of the actuator 14 by the hollow body 11.

[0079] Preferably, the movable body 13 comprises a so-called support zone. The actuator is in contact with the base 111 of the hollow body and the support zone of the movable body.

[0080] Preferably, the actuator 14 is a helical spring extending longitudinally along a longitudinal axis coaxial with the main axis 12. When the assistance device is held in the retracted position, the helical spring is compressed between the base 111 and the support zone of the mobile body 13. This compression generates, in reaction, a thrust on the support zone of the mobile body 13 capable of deploying the assistance device 10 in the deployed position when it is no longer held in the retracted position. Advantageously, the direction of this thrust and the main axis 12 are coaxial. By maintaining in the retracted position, we mean for example the exertion of an external force on the second connecting interface of the second end of the mobile body, directed along the main axis 12, of orientation opposite to that of the force generated by the actuator 14 and the intensity of which is at least equal to or greater than the intensity of the force generated by the actuator.In the preferred and non-limiting example of an aid device 10 intended to assist a user in pivoting a pivoting cover 20 relative to a frame 30, such an external force is induced by the positioning of the cover 20 in the closed position.

[0081] In one embodiment of the invention, the actuator 14 is a helical spring and the first end 131 of the movable body comprises the support zone of the movable body 13. Alternatively, the movable body 13 is configured so that the second end 132 of the movable body comprises the support zone of the movable body 13. For example, the movable body is cylindrical in shape and the section of the first end 131 is circular. The movable body is hollow, longitudinally, and thus has a hollow volume from the first end 131 to near the second end 132, as illustrated in [Fig.l].The longitudinal axis of the mobile body being coaxial with the main axis 12, it results that the hollow volume of the mobile body 13 creates coincides with or extends the internal volume 115 of the hollow body, thus forming a free space allowing the insertion of an actuator 14 of greater length (than in the absence of hollow volume in the mobile body 13, open onto the internal volume of the hollow body 11) in the aid device 10, between the base 111 of the hollow body and the second end 132 of the mobile body comprising the support zone, as illustrated in [Fig.l].

[0082] The assistance device 10 further comprises a two-state safety device 15, as illustrated in [Fig.4], namely a locked state and an unlocked state, said safety device being configured to: • when it is in the unlocked state (see [Fig.4]-b), authorize the translation of the mobile body 13 with respect to the hollow body, and • when in the locked state (see [Fig.4]-a), prevent the translation of the movable body 13 with respect to the hollow body, towards the retracted position of the opening assistance device.

[0083] The safety device 15 is positioned fixedly on the side wall of the hollow body. Advantageously, this results in a reduced size of the assistance device at the first connection interface 113 and at the second connection interface 133. Also, this positioning facilitates access to the safety device 15 by a user.

[0084] Preferably, the side wall of the hollow body 11 comprises an orifice 114 passing through the thickness of the hollow body, thus forming a lumen between the hollow volume 115 of the movable body and the exterior of the side wall of the hollow body, as illustrated in [Fig.3]. By exterior, we mean the surface of the side wall which is not in contact with the internal volume 115 of the hollow body.

[0085] In a preferred embodiment of the invention, the orifice 114 is circular around a central axis. For example, the orifice 114 is made by drilling. The diameter of the orifice is between 5mm and 130mm. The drilling is such that the central axis of the orifice 114 remains perpendicular to the main axis 12. The positioning of the orifice along the main axis 12 is such that: • the light formed by the orifice 114 is closed by the mobile body 13 when the assistance device 10 is not in the deployed position, as illustrated in [Fig.3](a), and • the light formed by the orifice 114 is not blocked by the mobile body 13 when the assistance device 10 is in the deployed position (the orifice is then released), as illustrated in [Fig.3](b).

[0086] In other words, the orifice 114 is made through the side wall of the hollow body, in direct proximity to the open end 112. By direct proximity, we mean a distance between 1 mm and 20 mm.

[0087] Also, the safety device 15 comprises a support 151 and a cylinder 152. Preferably, the support extends along an axis called the support axis. The support 151 comprises a light passing through it along the support axis. Preferably, the light is of circular section and of constant diameter, along the support axis. In a preferred embodiment of the invention, this light is centered on the support axis and the support axis is perpendicular to the main axis 12, once the safety device 15 is fixedly positioned on the side wall of the hollow body 11. For example, this light is produced by drilling the support.

[0088] Preferably, the base of the support 151 is rigidly connected to the side wall of the hollow body 11 so that the support axis is coaxial with the central axis of the orifice 114. As a variant, the end of the support 151 is rigidly connected to the side wall of the hollow body 11 so that the support axis is coaxial with the central axis of the orifice 114. As a result, the light of the support 151 is opposite the light of the orifice 114. The section of the light of the support 151 is preferably identical to the section of the light of the orifice 114.

[0089] Preferably, the support 151 is made of a rigid material. In a preferred embodiment of the invention, the support 151 and the side wall of the hollow body 11 are made of the same material. Advantageously, this results in a rigid connection that is easier to produce between, on the one hand, the side wall of the hollow body 11 and, on the other hand, the base or the end of the support 151. For example, the rigid connection is a weld.

[0090] Alternatively, the support 151 and the hollow body 11 can be in one piece.

[0091] The cylinder 152 is movable in translation relative to the support 151, between a position called entry and a so-called exit position. More precisely, the diameter and shape of the cylinder 152 are such that they ensure its translational mobility through the lumen of the support 151. The cylinder is made of a rigid material. Preferably, the cylinder is metallic, for example steel. Alternatively, the cylinder 152 is stainless steel.

[0092] The length of the cylinder 152 is greater than the resulting distance of the sum of the height of the support 151 (along the support axis) and the thickness of the side wall of the hollow body 11.

[0093] In the extended position, the length of the cylinder 152 is such that the cylinder passes through the support 151 and penetrates into the internal volume 115 of the hollow body 11, and extends opposite the side wall of the movable body 13 as illustrated in [Fig.4]-a. Preferably, the cylinder penetrates into the internal volume of the hollow body to a depth of between 1 and 15 millimeters. For example, the cylinder penetrates 8 millimeters into the internal volume of the hollow body. In the extended position, the depth of penetration of the cylinder into the internal volume of the hollow body advantageously allows the cylinder 152 to come into contact with a portion of the movable body 13 positioned in the internal volume 115 of the hollow body, as illustrated in [Fig.4]-a.

[0094] In a preferred embodiment of the invention, the safety device 15 is an indexing finger. An indexing finger comprising a cylindrical finger and a body through which said cylindrical finger is movable in translation. The cylindrical finger comprises two ends, one of which provides an interface with a user and the other of which provides indexing of an element in contact with it. By indexing, we mean a temporary blocking of the position of said element in contact with the end of the cylindrical finger.

[0095] The applicant carried out conclusive tests by adapting, as a safety device, an indexing finger marketed by the company NORELEM (France). The safety device used during these tests is marketed under the reference 03097-01308.

[0096] Obviously other references and other models of indexing finger can be used in an equivalent manner.

[0097] The movable body comprises at least one contact zone capable of ensuring rigid support with the part of the cylinder 152 in contact. This rigid support is such that it ensures the locked state of the safety device. In a preferred embodiment of the invention, the first end 131 comprises the at least one contact zone of the movable body. Advantageously, the locked state of the safety device 15 can be adopted when the assistance device 10 is in the deployed position.

[0098] Preferably, when the aid device is not in the deployed position, the lumen of the orifice 114 is closed by the movable body 13, as illustrated in [Fig.3](a). For example, the movable body, movable in translation in the internal volume 115 of the hollow body, is of cylindrical shape and its external wall closes the orifice 114 when the movable body is not in the second position, this position corresponding to the deployed position of the aid device 10. Advantageously, this closing of the orifice 114 prevents the cylinder 152 from penetrating into the internal volume of the hollow body 11. This ensures the entry position of the cylinder 152. In the entry position, illustrated in [Fig.3](b), no contact is formed between the cylinder 152 and the movable body 13 positioned in the internal volume of the hollow body. This absence of contact allows the free translation of the movable body 13 in the internal volume 115 of the hollow body.As a result, the entered position of the cylinder 152 ensures the unlocked state of the safety device 15. Advantageously, the locked state of the safety device is only possible when the assistance device 10 is in the deployed position.

[0099] Preferably, the safety device 15 comprises an elastic element on the one hand connected to the support 151 and on the other hand connected to the cylinder 152. For example, the elastic element is a spring. The elastic element is configured to generate a force which tends to bring the cylinder 152 into the extended position. Advantageously, this results in the safety device 15 spontaneously switching to the locked state when the opening assistance device 10 is in the deployed position.

[0100] In a preferred embodiment of the invention, in the extended position, the cylinder 152 compresses the elastic element, this compression generating in reaction a force capable of pushing the cylinder towards its entered position. In another embodiment of the invention, in the extended position, the cylinder 152 stretches the elastic element, this stretching generating in reaction a force capable of bringing the cylinder into the entered position.

[0101] Advantageously, the assistance device 10, as previously described, can be part of an access device 60 to an underground installation, as illustrated in FIGS. 5 and 6.

[0102] The invention is now described in the preferred and non-limiting example of an access device 60 comprising a frame 30, a cover 20 pivoting relative to a cover frame and an assistance device 10 intended to assist a user in said pivoting of the cover 20.

[0103] The frame 30, which will be described later, is configured to form an opening 32 positioned opposite a well, allowing access to an underground installation. The opening 32 of the frame forms a so-called access plane.

[0104] The cover 20, which will be described later, is pivotable along a longitudinal axis called the pivot axis 50. The cover is pivotable relative to the frame between a so-called open position and a so-called closed position, the cover being intended on the one hand to close access to the underground installation when it is positioned in the closed position and, on the other hand, to allow access when it is positioned in the open position.

[0105] The assistance device 10 moves between two positions, called retracted and unfolded. Between these two positions, the useful length of the assistance device 10 differs. In the retracted position, the useful length of the assistance device is minimal and in the deployed position, the useful length of the assistance device is maximal.

[0106] The cover 20 further comprises a first joining element 21 projecting from the cover. The frame 30 further comprises a second joining element 31 projecting from the frame. The assistance device 10 is intended to be connected to, on the one hand, the first joining element 21 of the cover and, on the other hand, to the second joining element 31 of the frame.

[0107] More specifically, the first connecting interface 113 of the base of the hollow body of the aid device 10 and the first joining element 21 of the cover 20 are configured to provide a first pivot connection between them. Also, the second connecting interface 133 of the second end of the aid device and the second joining element 31 of the frame 30 are configured to provide a second pivot connection between them.

[0108] Alternatively, the second connecting interface 133 of the second end of the aid device and the first joining element 21 of the cover are configured to provide a first pivot connection between them. Also, the first connecting interface 113 of the base of the hollow body of the aid device and the second joining element 31 of the frame are configured to provide a second pivot connection between them.

[0109] By pivot connection is meant a mechanical connection allowing rotation around an axis perpendicular or substantially perpendicular to the longitudinal axis 12 of the mobile body 13. In a preferred embodiment of the invention: • the first connecting interface 113 is a longitudinal extrusion of material from the base 111, in a longitudinal direction along the main axis 12, of constant thickness, positioned outside the internal volume 115 of the hollow body 11 and comprising an orifice passing through the thickness along an axis perpendicular to the main axis 12, • the first connecting element 21 of the cover comprises a first removable cylindrical rod and a first yoke or “two-pronged fork”, the first yoke projecting from the cover, its two branches being spaced apart by a space equivalent to the thickness of the first connecting interface 113 of the base of the hollow body, the two branches comprising a slot passing through the first fork from one side to the other along an axis perpendicular to the main axis 12, said slot being intended to accommodate the first cylindrical rod,

[0110] so that once the first connecting interface 113 is positioned between the branches of the first fork, the orifice of the first connecting interface 113 remains opposite the lumen of the branches of the first fork of the first connecting element 21 and that the insertion of the first cylindrical rod of the first connecting element through said lumen of the branches of the first fork also passes through said orifice. This results in a connection between the aid device 10 and the cover 20 which is simple to manufacture and rotational mobility is ensured around the first cylindrical rod.

[0111] In this same preferred embodiment of the invention: • the second connecting interface 133 extends at the level of the second end 132 in the longitudinal direction along the main axis 12, of constant thickness, and comprises a through orifice along an axis perpendicular to the main axis 12, • the second connecting element 31 of the frame comprises a second removable cylindrical rod and a second two-branch yoke, the second yoke projecting from the frame, its two branches being spaced apart by a space equivalent to the thickness of the second connecting interface 133 of the second end of the mobile body, the two branches comprising a slot passing through the second fork from one side to the other along an axis perpendicular to the main axis 12, said slot being intended to accommodate the second cylindrical rod,

[0112] so that once the second connecting interface 133 is positioned between the branches of the second fork, the orifice of the second connecting interface remains opposite the lumen of the branches of the second fork and the insertion of the second cylindrical rod of the second connecting element through said lumen also passes through said orifice. This results in a connection between the aid device 10 and the 30 frame is simple to manufacture and rotational mobility is ensured around the second cylindrical rod.

[0113] The pivoting of the cover takes place around the pivot axis 50. Preferably, this pivoting is guided by a hinge 40, as illustrated in [Fig. 5]. This hinge is formed on the one hand by a part of the cover 20 distinct from the first joining element 21 and, on the other hand, by a part of the frame distinct from the second joining element 31.

[0114] As a result, the first joining element 21 of the cover 20 and the second joining element 31 of the frame 30 are each positioned at a distance from the pivot axis 50, as illustrated in [Fig.5].

[0115] Preferably, the first joining element 21 of the cover and the second joining element 31 of the frame are configured so as to position the assistance device 10 of the access device 60 in a plane perpendicular to the access plane to the underground installation. As a result, the main axis 12 moves in this plane perpendicular to the access plane, whether the assistance device 10 is in the retracted position or in the deployed position.

[0116] This perpendicularity of the plane comprising the main axis 12 relative to the access plane and the support of the assistance device 10 on the frame are such that it results in a lever arm phenomenon ensuring the pivoting of the cover 20 as a function of the useful length of the assistance device 10. Advantageously, the assistance device 10 of the access device 60 controls the pivoting of the cover 20, so that: • When the assistance device 10 is in the retracted position, the cover 20 is in the closed position, and • When the aid device 10 is in the deployed position, the cover 20 is in the open position.

[0117] In addition, the actuator 14 of the assistance device 10 of the access device 60 being configured to generate a force which tends to bring the opening assistance device into the deployed position, it follows that the access device 60 is able to assist a user to pivot the cover 20 to its open position.

[0118] As described above, the safety device 15 of the opening assistance device 10 is rigidly fixed to the side wall of the hollow body of the assistance device. This results in an access device 60 in which the safety device 15 of the assistance device 10 remains distant from the pivot axis 50 of the cover 20 and distant from the access opening to the underground installation. Advantageously, the access device 60 clears the access opening to the underground installation. Also, the access device 60 facilitates the operation of securing a cover in the open position. Indeed, the safety device 15 of the assistance device 10 of the access device 60 remains positioned away from the access plan and is therefore more accessible to a user.

[0119] Also, this results in increased compatibility of the access device 60 with an underground installation of small size and / or depth because: • the useful length of the assistance device 10 of the access device 60 is dimensioned to the exact need associated with the pivoting of the cover 20, • the pivot connections, as described previously, between on the one hand a part of the cover and a part of the assistance device and, on the other hand, between a part of the assistance device and a part of the frame 30, ensure that in the retracted position the main axis 12 of the assistance device is substantially parallel to the access plane. The assistance device 10 of the access device 60 therefore does not penetrate deeply into the underground installation.

[0120] Before use, the frame 30 of the access device 60 is fixed in the ground, on an access shaft to the underground installation.

[0121] The cover 20 of the access device 60 is in the closed position and the safety device 15 of the assistance device 10 of the access device 60 is considered to be in the unlocked state. This assistance device 10 is further held in the retracted position by the cover. By being held in the retracted position, a force is exerted on the second interface connecting the second end of the movable body of coaxial direction to the main axis 12, in an orientation opposite to that of the force generated by the actuator 14. The intensity of this force is equal to or greater than the intensity of the force generated by the actuator. The useful length of the assistance device 10 is minimal in the retracted position.

[0122] In use, a user of the access device 60 initially actuates the cover 20. For example, the user initiates the pivoting of the cover 20 around the pivot axis 50. This actuating induces a resulting force along the main axis 12. This resulting force is such that once added to the force generated by the actuator 14 of the assistance device 10, it allows the assistance device 10 to exit the previous holding state. The force generated by the actuator, added to the initial actuating of the user, then brings the assistance device into the deployed position. Advantageously, the user is assisted when opening the cover 20.

[0123] This assistance is carried out until the assistance device 10 reaches its deployed position. In the deployed position, the useful length of the assistance device 10 is maximum. Advantageously, this results in the cover reaching its open position.

[0124] In a second step, the assistance device 10 of the access device 60 being in the deployed position, the safety device 15 of said assistance device is switched from the unlocked state to the locked state, prohibiting any translational mobility of the mobile body of the aid device.

[0125] The switching of the safety device can be carried out by the user of the access device 60 by directly pressing the cylinder 152 of the safety device until it is brought into the extended position. Alternatively, the switching of the safety device is carried out automatically by the safety device 15 when configured to spontaneously switch to the locked state.

[0126] This locked state ensures that the assistance device 10 is kept in the deployed position. The cover 20, now in the open position, can advantageously no longer pivot around the pivot axis 50. This results in the cover 20 being secured in the open position.

[0127] At the end of use, the user brings the cover 20 of the access device 60 to its closed position.

[0128] In order to allow the lid 20 to be closed, the user exerts traction on the cylinder 152 of the safety device, which brings it into the retracted position. The translation of the movable body 13 in the hollow body 11 is then permitted, in order to bring the assistance device towards its retracted position. In particular, the pivoting of the lid from the open position to the closed position causes the passage of the assistance device 10 of the access device 60 from the deployed position to the retracted position. When the actuator 14 of the assistance device 10 of the access device 60 is a helical spring, this passage further causes the compression of the actuator 14 along the main axis 12. In reaction, the actuator 14 of the assistance device of the access device 60 generates a thrust opposite to the direction of pivoting of the lid. The sizing of the actuator 14 is such that this thrust reduces the impact of the weight of the cover 20 on the user.This reduces the weight the user has to bear when closing the lid, and prevents it from falling violently onto the frame. . .

[0129] Alternatively, the access device 60 further comprises several covers 20 and a frame 30 delimiting an opening 32. In a non-limiting manner, [Fig. 6] illustrates such an access device with two covers 20. Each cover comprises a first joining element 21.

[0130] Preferably, each cover is linked to an aid device 10 and the frame 30 comprises as many second joining elements 31 as there are aid devices 10. More precisely, each first joining element 21 is linked by pivot connection to one of the two connecting interfaces of at least one opening aid device 10. The other of the two connecting interfaces of each aid device 10 is linked by pivot connection to one of the second joining elements 31. In a preferred embodiment of the invention, each aid device is positioned at the periphery of the access device 60.

[0131] Advantageously, this results in easier access for the user to each aid device 10 of the access device 60 and therefore easier access for the user to the safety device 15 of each aid device 10 of the access device 60. The user can thus easily lock or unlock the safety device 15, without having to lean over the opening 32.

[0132] Also, this results in improved access to the underground installation insofar as the opening assistance and safety functions are grouped on the sides of the frame 30, without a central crosspiece being necessary to provide supports for the opening assistance or safety devices of the access device 60.

[0133] The present invention thus proposes a device for assisting in opening a pivoting manhole cover which combines the function of assisting in opening and securing the cover in the open position. This is achieved using a simple safety device, installed directly on the opening aid device. The invention limits the obstacles to access to the underground infrastructure located under the access device. The opening aid device proposed in the invention is particularly simple and inexpensive. Finally, it makes it possible to equip access devices initially comprising only an opening aid device, but no securing device, with a securing function.

Claims

Claims

1. Opening assistance device (10) for a pivoting manhole cover intended to equip an underground installation, the opening assistance device comprising: • a hollow body (11) comprising a base (111), an open end (112) and a side wall between said and said open end, the hollow body delimiting an internal volume (115), the hollow body extending longitudinally between the base and the open end along a longitudinal axis called the main axis (12), the base (111) comprising a first connecting interface (113), • a mobile body (13) comprising a first end (131) and a second end (132), the second end comprising a second connecting interface (133), at least the first end (131) being contained in the internal volume of the hollow body (11), the mobile body being mobile in translation along the main axis (12), so that the opening assistance device can take on the one hand, a so-called retracted position in which the distance between the first connecting interface (113) and the second connecting interface (133) is minimal and, on the other hand, a so-called deployed position where said distance between the first connecting interface (113) and the second connecting interface (133) is maximal, an actuator (14) configured to generate a force which tends to bring the opening assistance device into the deployed position, a two-state safety device (15), namely a locked state and an unlocked state, said safety device being configured to: • when in the unlocked state, authorize the translation of the mobile body (13) with respect to the hollow body, and • when in the locked state, prohibit the translation of the movable body (13) with respect to the hollow body, towards the retracted position of the opening assistance device,

2.

3.

4.

5. characterized in that the safety device (15) is rigidly connected to the side wall of the hollow body (11), and in that: • the side wall of the hollow body (11) comprises a through orifice (114), • the safety device (15) comprises a support (151), fixed to the wall of the hollow body, a cylinder (152), the cylinder being movable in translation relative to the support (151) between: • a so-called entry position in which the cylinder is is completely outside the internal volume delimited by the hollow body, and • a so-called extended position in which the cylinder extends through the orifice (114) in the side wall of the hollow body, and • the mobile body (13) comprises at least one contact zone and capable of providing support on the cylinder in the extended position, so that when the cylinder is in the in position the safety device is unlocked and when the cylinder is in the out position the safety device is locked. An opening aid device (10) according to claim 1, wherein the at least one contact zone of the movable body (13) is formed by the first end (131) of the movable body. An opening aid device (10) according to claim 1 or claim 2, wherein the movable body (13) obstructs the orifice (114) in the side wall of the hollow body when the opening aid device is in the retracted position and clears the orifice (114) in the side wall of the hollow body when the opening aid device is in the deployed position. Opening assistance device (10) according to one of claims 1 to 3, wherein the actuator (14) is a helical spring. Opening assistance device (10) according to one of claims 1 to 4, wherein the actuator (14) is at least partly contained in the internal volume of the hollow body (11), the actuator extending between the base (111) of the hollow body and a bearing surface of the movable body (13).

6. An opening assistance device (10) according to claim 5, wherein said bearing surface of the movable body (13) is formed by the first end (131).

7. An opening aid device (10) according to claim 5, wherein the movable body (13) is configured such that the bearing surface of the movable body is formed by the second end (132).

8. An opening assistance device (10) according to one of claims 1 to 7, wherein the safety device (15) is configured to spontaneously switch to the locked state when the opening assistance device (10) is in the deployed position.

9. Access device (60) to an underground installation comprising a cover (20), a frame (30), the cover being connected to the frame, and an opening assistance device (10) according to one of claims 1 to 8, in which: • the cover (20) is pivotable with respect to the frame between a so-called open position and a so-called closed position, the cover being intended on the one hand to close access to an underground installation when it is positioned in the closed position and, on the other hand, to allow access when it is positioned in the open position, • the cover (20) comprises a first connecting element (21) capable of ensuring a pivot connection with one of the two connecting interfaces among the second connecting interface (133) of the second end of the movable body of the opening assistance device (10) and the first connecting interface (113) of the base of the hollow body of the opening assistance device (10),• the frame (30) forms an opening for access to an underground installation, the frame comprises a second connecting element (31) capable of ensuring a pivot connection with the other of the two connecting interfaces among the second connecting interface (133) of the second end of the mobile body of the opening assistance device (10) and the first connecting interface (113) of the base of the hollow body of the opening assistance device (10).,

10. An access device (60) according to claim 9 configured so that when the cover (20) is in the closed position, the opening aid device (10) is in the retracted position, and when the

11. cover is in the open position, the opening aid device is in the deployed position. Access device (60) according to claim 9 or claim 10, comprising several covers (20) and a single frame (30), each cover being associated with an opening assistance device (10) according to one of claims 1 to 8.

Images