Pressurization system for a mobile mechanism operating in a potentially explosive atmosphere

Abstract

Pressurization System for a Mobile Mechanism Operating in a Potentially Explosive Atmosphere. The present invention relates to a pressurization system (40) for a mobile mechanism comprising a body including an outer casing (20) defining an internal volume (25). The pressurization system is mounted on the mobile mechanism and configured to maintain a pressurizing fluid (45) under pressure in a gaseous state within the internal volume. The pressurization system includes a fluid storage tank (50) and a fluidic circuit (55) fluidically connecting the storage tank to the internal volume for injecting a quantity of pressurizing fluid into the internal volume. The pressurizing fluid (45) is stored in the storage tank (50) in a liquid state. The pressurizing fluid (45) changes to a gaseous state when injected into the internal volume (25). Figure for the abstract: 2

Description

Title of the invention: Pressurization system for a mobile mechanism operating in a potentially explosive atmosphere

[0001] The present invention relates to a pressurization system applied to a mobile mechanism such as a robot.

[0002] Many oil installations are intended to become uninhabited for long periods, in particular to reduce emissions generated by the presence and / or transport of human operators on the sites and to reduce their exposure to the risks inherent in this type of installation.

[0003] In order to ensure the proper functioning of oil installations, mobile mechanisms, for example autonomous and / or remotely operated robots, are installed on the sites.

[0004] Robots are for example charged with carrying out inspection, maintenance and production tasks such as collecting and / or transmitting information related to the operation of the installations (video recording, taking measurements, detecting the presence of gas, etc.) and / or carrying out manipulations for the operation and / or maintenance of the installations, in order to ensure the proper functioning and safety of the oil site.

[0005] For this purpose, the robots are generally mobile in order to move to the measurement points and / or to perform manipulations in precise locations of the site, and operate on an electric battery.

[0006] On petroleum installations (or other types of installations, including chemical or food processing installations), under certain conditions, explosive atmospheres may form due to the presence of flammable substances and / or dust.

[0007] Thus, the mechanisms to be deployed in these potentially explosive atmosphere zones must comply, depending on the region, with ATEX and / or ECEx standards, for example, in order to avoid triggering an explosion that could have serious consequences for the installation. In particular, robots, and any other components located in these potentially explosive atmosphere zones, must comply with the standards of the IEC 60079 family.

[0008] To ensure the proper functioning of robots in ATEX zones, the selection of the equipment protection method according to the hazardous areas is carried out, for example, on the basis of standard EN 60079-10. One protection method consists of maintaining the internal volume of the robot under positive pressure relative to the surrounding atmosphere. The The internal overpressure protection method is notably subject to the EN 60079-2 standard.

[0009] In order to pressurize the interior of the robot, a gas is injected inside the robot to create an overpressure relative to the external pressure. This prevents the infiltration of the potentially explosive surrounding atmosphere into the robot.

[0010] The injection of gas inside the robot is then done on site, for example by connecting the robot, during battery charging, to an available pressurized source such as nitrogen or dry air, for example, or, in less frequent cases, by a bottle filled with gas carried on the robot, or even by injecting ambient air directly into the robot.

[0011] However, when the pressurization system uses an on-board cylinder, the on-board gas cylinder must be recharged or replaced when empty, which requires the cylinder to be replaced more or less frequently by an operator and / or the provision of gas recharging systems distributed throughout the installation.

[0012] In addition, when gas injection is carried out on site by connecting the robot to an available pressurized source, it is necessary to repressurize the robot frequently, and therefore to provide many gas loading points on site.

[0013] Finally, when ambient air is injected directly into the robot, it is first necessary to ensure that it is not an explosive gas. Furthermore, there is a risk of injecting humid gas if the ambient air contains moisture, which can impair the proper functioning of the robot.

[0014] One of the aims of the invention is therefore to propose a pressurization system for a mobile mechanism capable of working in a potentially explosive atmosphere, the pressurization system having a greater autonomy.

[0015] To this end, the invention relates to a pressurization system for a mobile mechanism, in particular a robot, the mobile mechanism comprising a body including an external envelope defining an internal volume, the pressurization system being mounted on the mobile mechanism and configured to maintain a pressurization fluid under pressure in the gaseous state in the internal volume, the pressurization system comprising a fluid storage tank and a fluidic circuit fluidically connecting the storage tank to the internal volume to inject a quantity of pressurization fluid from the storage tank into the internal volume.

[0016] Since the pressurization fluid is stored in a storage tank in liquid form, a greater quantity of fluid can be stored compared to a fluid stored in gaseous form, and the moving mechanism can operate for longer between two refills of pressurization fluid.

[0017] According to other advantageous aspects of the invention, the pressurization system comprises one or more of the following optional features, taken individually or according to all technically possible combinations:

[0018] - the pressurization fluid is a dry fluid and is chosen from dioxide carbon, halogenated gases or a mixture thereof;

[0019] - the fluidic circuit includes a calibrated fluid storage space, the circuit fluidic being configured to sequentially transfer pressurization fluid in liquid state from the storage tank to the calibrated storage space and then transfer the pressurization fluid from the calibrated storage space to the internal volume;

[0020] - the calibrated storage space is sequentially fluidly isolated from the volume internal of the moving mechanism during the transfer of the pressurization fluid in liquid state from the storage tank to the calibrated storage space, and fluidly isolated from the storage tank during the transfer of the pressurization fluid from the calibrated storage space to the internal volume;

[0021] - the fluidic circuit includes a fluidically arranged injection valve between the calibrated storage space and the internal volume to control the circulation of the pressurization fluid from the calibrated storage space to the internal volume;

[0022] - the injection valve is a three-way valve comprising a first position allowing the storage tank to be fluidly connected to the calibrated storage space to fill the calibrated storage space with pressurizing fluid and a second position allowing the calibrated storage space to be fluidly connected to the internal volume to inject the pressurizing fluid into the internal volume;

[0023] - the injection valve is a simple valve, the calibrated storage space being defined in the fluidic circuit upstream of the injection valve, the closing of the injection valve fluidly isolates the calibrated storage space from the internal volume, the opening of the injection valve fluidly connects the calibrated storage space to the internal volume for the injection of the pressurizing fluid into the internal volume;

[0024] - the fluidic circuit includes a normally closed isolation valve, located in upstream of the normally closed injection valve;

[0025] - the calibrated storage space is defined between the isolation valve and the valve injection;

[0026] - the isolation valve is controlled according to a measurement signal from a first pressure sensor representative of the pressure inside the internal volume, in order to secure the internal volume of the moving mechanism, and the injection valve is controlled according to the opening and closing of the isolation valve;

[0027] - a second pressure sensor arranged to measure the pressure inside the storage tank; and

[0028] - the fluidic circuit includes a system for slowing down the expansion of the fluid pressurization injected into the internal volume.

[0029] According to yet another aspect, the invention relates to a pressurization method for a mobile mechanism, implementing such a pressurization system, comprising the steps of: - to store a pressurization fluid in liquid form in a storage tank mounted on the mobile mechanism, - inject a quantity of pressurizing fluid from the storage tank into the internal volume of the moving mechanism, the injected pressurizing fluid changing from a liquid to a gaseous state, to maintain pressurization of the internal volume of the moving mechanism using the pressurizing fluid.

[0030] According to other advantageous aspects of the invention, the pressurization process comprises one or more of the following optional features, taken individually or in all technically possible combinations:

[0031] - the pressurization fluid is dry and is chosen from carbon dioxide, gases halogenated substances, or a mixture thereof; and

[0032] - the injection step is carried out sequentially by transferring the quantity of fluid pressurization of the storage tank to a storage space and then by injecting the quantity of pressurization fluid contained in the calibrated storage space into the internal volume.

[0033] The invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0034] [Fig-1] [Fig.1] is a schematic external representation of a moving mechanism, in particular a robot,

[0035] [Fig.2] [Fig.2] is a schematic internal representation of the moving mechanism,

[0036] [Fig.3] [Fig.3] is a schematic representation of the storage systems of the pressurization fluid and pressurization systems of the moving mechanism according to a first embodiment, and

[0037] [Fig.4] [Fig.4] is a schematic representation of the pressurization fluid storage systems and the pressurization systems of the moving mechanism according to a second embodiment.

[0038] Fig. 1 schematically represents a moving mechanism.

[0039] By "mobile" it is understood that the mechanism is capable of moving on a floor or in stairs by translation and / or that the mechanism includes a part that is movable relative to at least one other part of the mechanism, such as an arm that is movable relative to the body of the mechanism for example.

[0040] In particular, the mobile mechanism is a robot 10, although the mobile mechanism may be any other kind of device capable of moving.

[0041] A robot is defined as a mechatronic device designed to perform specific tasks, imitating or reproducing human actions.

[0042] The robot 10 is configured for example to collect and / or transmit information related to the operation of an industrial installation as a substitute for or in addition to a human presence.

[0043] The robot 10 is for example equipped to take videos, photos, measurements and / or physically interact with the installation by taking samples for example and to transmit a certain amount of information to a remote operator and / or to a remote control center.

[0044] The robot 10 is, for example, autonomous and / or remotely operable by an operator. When autonomous, the robot 10 is capable of performing missions autonomously, without external intervention.

[0045] The robot 10 includes, for example, an electric battery sufficient to ensure the autonomy and proper functioning of the robot.

[0046] The robot 10 is, for example, designed to operate in areas with potential explosion risks, for example on oil installation sites.

[0047] Of course, such a robot 10 could operate on any other type of industrial installation and is not limited to use in the oil sector.

[0048] The robot 10 comprises a body 15.

[0049] The body 15 of the robot 10 comprises an external envelope 20 defining an internal volume 25.

[0050] The envelope 20 is for example made of a rigid material, such as a metallic or other material.

[0051] The internal volume 25 has a residual volume that is a function of the volume of the envelope 20 and the components installed inside the robot 10, for example between 0.001 m3 and 0.1 m3.

[0052] In exemplary embodiments, the robot body 15 comprises a base 28 and one or more functional organs 30 mounted on the base 28. Each functional organ 30 is configured to perform one or more functions.

[0053] Each functional component 30 is mounted fixed or movable on the base 28.

[0054] Each functional organ 30 contains, for example, electrical components.

[0055] The outer casing 20 of the robot 10 includes the base 28 and each functional organ 30.

[0056] As illustrated in [Fig.1], the robot 10 includes, for example, a functional organ 30 which is a turret, which is, for example, mobile relative to the base 28, in particular rotating relative to the base 28. The functional organ 30 accommodates, for example, a measuring system and / or an image capture system.

[0057] The measuring system is configured, for example, to measure one or more distances, pressure, temperature, the concentration of one or more chemical compounds in the surrounding atmosphere, or to detect and / or measure a sound signal (frequency, amplitude), ...

[0058] Alternatively or as an option, a functional organ 30 of the robot 10 is an articulated arm, preferably carrying a tool for performing operations, such as for example a gripper or a robotic hand.

[0059] In exemplary embodiments, the robot 10 includes a locomotion system 35 configured to enable the robot 10 to move. The locomotion system 35 includes, for example, tracks as shown in [Fig. 1].

[0060] As an alternative or in addition, the movement system 35 includes wheels and / or articulated legs.

[0061] In general, the robot 10 includes a movement system 35 allowing the robot 10 to move in several directions, on floors of various types and with varying levels of inclination or stairs.

[0062] The displacement system 35 is for example mounted on the base 28 of the robot 10 and located outside the outer envelope 20.

[0063] As illustrated in [Fig.2], in embodiment examples, the robot 10 includes a pressurization system 40 mounted on the robot 10 and configured to maintain a pressurization fluid 45 in a gaseous state under pressure in the internal volume 25.

[0064] By "onboard" it is understood that the pressurization system 40 is mounted on the robot 10 in such a way that it is moved with the robot 10.

[0065] The pressurization fluid 45 is preferably a dry fluid. "Dry" means that the dew point of the fluid (the temperature to which the fluid must be cooled for the water vapor it contains to condense) is, for example, 20°C lower than the minimum ambient operating temperature of the fluid. Generally, the dew point of the fluid 45 must be sufficiently low relative to the operating temperature of the pressurization fluid 45 to prevent condensation of water vapor inside the casing 20, which could impair the operation of the robot 10.

[0066] The pressurization fluid 45 is chosen to ensure the safety and integrity of the electronic equipment, in particular to be non-corrosive towards the electronic or other components of the robot 10.

[0067] The pressurization fluid 45 is preferably chosen from fluids that can be stored in a liquid state at ambient temperature and under moderate pressure.

[0068] For example, the pressurization fluid 45 is chosen from carbon dioxide, halogenated gases such as, for example, 1,1,1,2,3,3,3-heptafluoropropane, trifluoro-rometane, perfluorobutane, or a mixture of these.

[0069] Preferably, the pressurization fluid 45 is carbon dioxide.

[0070] The pressurization system 40 is intended to maintain the internal volume 25 of the robot 10 under pressure by injecting the pressurization fluid 45 in a gaseous state into the internal volume 25.

[0071] For example, the pressurization system 40 is configured to maintain an overpressure between 10 mbar and 200 mbar, for example between 40 mbar and 60 mbar in the internal volume 25 of the robot 10 relative to the surrounding atmosphere.

[0072] This then allows the robot 10 to operate in particular in areas at risk of explosion as described above.

[0073] Since the internal volume 25 of the robot 10 is pressurized relative to the atmosphere surrounding the robot 10, an infiltration of potentially explosive surrounding atmosphere into the robot 10 is avoided.

[0074] The pressurization system 40 includes a storage tank 50 for the pressurization fluid 45.

[0075] The storage tank 50 is for example a pressurized bottle, having a capacity depending in particular on the space available on the robot 10, the additional weight that can be carried on the robot 10, or depending on the desired pressurization time.

[0076] The storage tank 50 is configured to store the pressurization fluid 45 in liquid form, the pressurization fluid 45 passing into a gaseous state when it is expanded and injected into the internal volume 25.

[0077] Since the pressurization fluid 45 is stored in liquid form, a significant quantity of pressurization fluid 45 can be stored in the storage tank 50.

[0078] This feature allows the robot 10 to operate for a longer period, because the storage tank 50 needs to be recharged with pressurization fluid 45 less frequently.

[0079] Advantageously, the pressurization fluid storage tank 50 is housed inside the outer casing 20.

[0080] Thus, the fluid exchanges between the inside of the outer envelope 20 and the outside of the robot 10 are limited to the strictly necessary exchanges as will be described in more detail later.

[0081] The storage tank 50 is equipped with a refill valve 52, preferably located on the outer casing 20.

[0082] The recharging valve 52 is arranged to fluidly connect the storage tank 50 to a pressurizing fluid recharging system 45, not shown, located outside the outer casing 20 of the robot 10, when the robot 10 needs to be recharged with pressurizing fluid 45, and to fluidly isolate the storage tank 50 from the outside of the robot 10 when the robot 10 is in operating mode and does not need to be recharged with pressurizing fluid 45.

[0083] The pressurization fluid recharge system 45 preferably contains the fluid pressurization fluid 45 is in liquid form. Therefore, the pressurization fluid refill system 45 can more easily hold a greater quantity of pressurization fluid 45 than the quantity of pressurization fluid 45 stored in the same volume in gaseous form. Consequently, the pressurization fluid refill system 45 is capable of refilling the storage tank 50 repeatedly.

[0084] The pressurization system 40 includes a fluidic circuit 55 fluidically connecting the storage tank 50 to the internal volume 25 to inject a quantity of pressurization fluid 45 from the storage tank 50 into the internal volume 25.

[0085] The fluidic circuit 55 is preferably configured for a gravity flow of the pressurization fluid 45 from the storage tank 50 to the internal volume 25.

[0086] Since the pressurization fluid 45 is stored in the storage tank 50 in liquid form, it is possible to simplify the fluidic circuit 55 by using gravity as a system for moving the pressurization fluid 45.

[0087] The fluidic circuit 55 notably consists of a fluidic line 57 for circulating the pressurization fluid 45 connecting the storage tank 50 to the internal volume 25.

[0088] The outlet of the storage tank 50 is for example located at the bottom, relative to a vertical axis, of the storage tank 50, and the fluidic line 57 extends downwards from the outlet of the storage tank 50.

[0089] In an alternative, not shown, the fluidic circuit 55 includes a draw-off tube inside the storage tank 50 in order to recover the pressurization fluid 45 at the bottom of the storage tank 50, for example if gravity flow is not used.

[0090] With reference to [Fig.3], a first embodiment of the pressurization system 40 of the robot 10 will now be described in detail.

[0091] In this embodiment, the fluidic circuit 55 advantageously includes a calibrated storage space 60 configured for temporary storage of a volume of pressurizing fluid 45 in liquid state, between the storage tank 50 and the internal volume 25.

[0092] In particular, the fluidic circuit 55 is configured for a gravity flow of the pressurization fluid 45 in liquid state from the storage tank 50 to the temporary calibrated storage space 60 and then for a gravity flow of the pressurization fluid 45 from the temporary calibrated storage space 60 to the internal volume 25.

[0093] The calibrated storage space 60 defines a storage volume adapted, and previously determined, to a quantity of pressurizing fluid 45 to be injected in the internal volume 25 of robot 10.

[0094] The fluidic circuit 55 is configured to sequentially transfer pressurization fluid 45 in liquid state from the storage tank 50 to the calibrated storage space 60 and then transfer the pressurization fluid 45 from the calibrated storage space 60 to the internal volume 25.

[0095] Preferably, the calibrated storage space 60 is fluidly isolated from the internal volume 25 of the robot 10 during the transfer of the pressurization fluid 45 in liquid state from the storage tank 50 to the calibrated storage space 60, and the calibrated storage space 60 is fluidly isolated from the storage tank 50 during the transfer of the fluid from the calibrated storage space 60 to the internal volume 25.

[0096] The quantity of pressurization fluid 45 injected into the internal volume 25 is precisely calibrated according to the volume of the calibrated storage space 60.

[0097] It may be possible to design a relatively small calibrated storage space 60 in order to regularly inject a small quantity of pressurizing fluid 45 into the internal volume 25, or to design a larger calibrated storage space 60 in order to inject less frequently a larger quantity of pressurizing fluid 45 into the internal volume 25.

[0098] The configuration of the calibrated storage space 60 can be determined in advance by the designer or manufacturer for each type of robot 10 for example.

[0099] For example, the calibrated storage space 60 defines an intermediate storage volume whose capacity is calibrated and a function of the internal volume 25.

[0100] Since the injection of pressurization fluid 45 into the internal volume 25 generally involves very small quantities of pressurization fluid 45, on the order of a few grams, it is advantageous to provide such an intermediate calibrated storage space 60.

[0101] The implementation of an intermediate calibrated storage space 60 makes it possible to simplify the fluidic circuit 55 in that it does not require a precise measurement system for the quantity of pressurization fluid 45 injected into the internal volume 25, which is automatically determined by the volume of the calibrated storage space 60.

[0102] The fluidic circuit 55 includes, for example, a set of valves having one or more valves arranged to sequentially transfer pressurization fluid 45 in liquid form from the storage tank 50 to the calibrated fluid storage space 60 and then transfer the pressurization fluid 45 from the calibrated fluid storage space 60 to the internal volume 25.

[0103] The valve assembly is arranged along the fluidic line 57 of the fluidic circuit in order to control the circulation of the pressurization fluid 45 inside the fluidic line 57.

[0104] The valve assembly is also arranged to control the quantity of pressurization fluid 45 injected from the storage tank 50 into the internal volume 25.

[0105] The fluidic circuit 55 includes, for example, an injection valve 65 arranged fluidically between the calibrated storage space 60 and the internal volume 25 to control the circulation of the pressurization fluid 45 from the calibrated storage space 60 to the internal volume 25.

[0106] In the example illustrated in [Fig.3], the injection valve 65 is a three-way valve 65A, 65B, 65C.

[0107] The injection valve 65 includes for example a first channel 65A fluidly connected to the storage tank 50, a second channel 65B fluidly connected to the calibrated storage space 60 and a third channel 65C fluidly connected to the internal volume 25.

[0108] In other words, the first position fluidly connects the storage tank 50 to the calibrated storage space 60 to fill the calibrated storage space 60 with pressurization fluid 45 in liquid form and the second position fluidly connects the calibrated storage space 60 to the internal volume 25 to inject the pressurization fluid 45 into the internal volume 25 in gaseous form.

[0109] In one embodiment, illustrated in particular in [Fig.3], the fluidic circuit 55 advantageously includes an isolation valve 70 located upstream of the injection valve 65.

[0110] The isolation valve 70 is advantageously located below the storage tank 50, so that the fluid 45 contained in the storage tank 50 simply flows by gravity in the fluid line 57 to the isolation valve 70.

[0111] The isolation valve 70 is for example a motorized valve, in the closed position by default.

[0112] The isolation valve 70 is, for example, a simple valve. By "simple," it is understood that the isolation valve 70 comprises an upstream inlet and a downstream outlet.

[0113] The isolation valve 70 isolates the storage tank 50, preventing the internal volume 25 from increasing in pressure, thereby putting the robot 10 into a safe state. To this end, the isolation valve 70 controls the flow of the pressurization fluid 45 from the storage tank 50 to the injection valve 65.

[0114] The isolation valve 70 and the injection valve 65 are, for example, controlled by an electronic control system.

[0115] The electronic control system includes, for example, an electrical control unit 72 and a first pressure sensor 75.

[0116] The first pressure sensor 75 is used to control the pressure in the internal volume 25.

[0117] The isolation valve 70 is for example controlled by the electronic control unit 72 according to a measurement signal from the first pressure sensor 75 representative of the pressure inside the internal volume 25 of the robot 10.

[0118] The first pressure sensor 75 is connected to the isolation valve 70 and to the electrical control unit 72 which receives the measurement signal and triggers the opening or closing of the isolation valve 70 according to the pressure measured in the internal volume 25.

[0119] The injection valve 65 is in particular controlled according to the opening and closing of the isolation valve 70.

[0120] In this embodiment, the calibrated storage space 60 is linked to the second channel 65B of the injection valve 65.

[0121] During the circulation of the pressurization fluid 45 from the storage tank 50 to the calibrated storage space 60, the first and second ways 65A, 65B are opened to allow the pressurization fluid 45 to circulate from the storage tank 50 to the calibrated storage space 60 and the third way 65C of the injection valve 65 is closed.

[0122] Thus, the calibrated storage space 60 of fluid 45 is fluidly isolated from the internal volume 25 of the robot 10 during the transfer of the pressurization fluid 45 in the liquid state from the storage tank 50 to the calibrated intermediate storage space 60.

[0123] Similarly, when injecting the pressurization fluid 45 from the calibrated storage space 60 into the internal volume 25, the first channel 65A is closed and the second and third channels 65B, 65C are opened to allow the fluid to flow from the calibrated storage space 60 into the internal volume 25.

[0124] Thus, the calibrated fluid storage space 60 is fluidly isolated from the fluid storage tank 50 during the transfer of the pressurization fluid 45 from the calibrated fluid storage space 60 to the internal volume 25.

[0125] Alternatively, the fluidic circuit does not include an isolation valve 70.

[0126] When the pressurization fluid 45 is injected into the internal volume 25, the fluid pressurization fluid 45 undergoes a change of state because the pressure inside the internal volume 25 is substantially lower than the pressure at which the pressurization fluid 45 was stored in the liquid state.

[0127] This pressure difference causes the pressurization fluid 45 to expand, which consequently tends to cool down.

[0128] In order not to disrupt the operation of the first pressure sensor 75 during the injection of the pressurization fluid 45 into the internal volume, the fluidic circuit 55 includes, for example, a system for slowing down 78 the expansion of the pressurization fluid 45 injected into the internal volume 25.

[0129] This system 78 makes it possible to slow down the expansion of the pressurization fluid 45 which is injected into the internal volume 25 where the pressure is lower than that at which it was stored in liquid form.

[0130] For example, system 78 is a heat exchanger, intended to moderate the drop in temperature of the pressurization fluid 45 during its injection into the internal volume 25.

[0131] The system for slowing down the expansion of the pressurizing fluid 45 78 is for example located fluidically between the set of valves and the internal volume 25.

[0132] The deceleration system 78 includes, for example, an expansion conduit 79, schematically represented in [Fig.3], configured to decelerate the expansion of the pressurization fluid 45. The expansion conduit 79 is, for example, serpentine in shape to promote heat exchange between the pressurization fluid 45 circulating in the expansion conduit 79 and the internal volume 25.

[0133] The electronic control system includes, for example, a second pressure sensor 80 arranged to measure the pressure inside the storage tank 50.

[0134] Advantageously, the second pressure sensor 80 is connected to the electrical control unit 72.

[0135] The second pressure sensor 80 provides, for example, via the electrical control unit 72, information to an operator and / or a control station on the quantity of pressurizing fluid 45 remaining inside the storage tank 50.

[0136] Alternatively, the second pressure sensor 80 is connected via a control box, not shown, different from the electrical control unit 72.

[0137] For example, the pressure inside the storage tank 50 is between 50 bar and 200 bar between two filling operations of the storage tank 50.

[0138] When the storage tank 50 no longer contains enough pressurizing fluid 45 in liquid phase, the pressure inside the storage tank 50 drops rapidly to a low value.

[0139] Such a drop in pressure is quickly detected by the second pressure sensor 80 which transfers, for example via the electrical control unit 72, the information to an operator and / or a control station.

[0140] Thus, the robot operator is quickly informed in case of a low quantity of pressurization fluid 45 remaining in the storage tank 50 and can plan an efficient refill of the storage tank 50 with pressurization fluid 45.

[0141] A second example of an embodiment of the pressurization system 40 of the robot will now be described, with reference to [Fig.4].

[0142] This second embodiment differs from that of Figure 3 in that the injection valve 65 is a simple valve.

[0143] The calibrated storage space 60 is then defined in the fluidic circuit 55 upstream of the injection valve 65, and downstream of the isolation valve 70.

[0144] The upstream of the valve 65 is fluidly connected to the calibrated storage space 60.

[0145] The downstream of the valve 65 is fluidly connected to the internal volume 25 of the robot 10.

[0146] This second embodiment also differs from that of [Fig.3] in that the storage tank 50 is located outside the outer casing 20, and not inside.

[0147] The storage tank 50 is however still carried on the robot 10.

[0148] This configuration allows the empty storage tank 50 to be replaced by another full storage tank instead of refilling the storage tank 50 with pressurization fluid 45 when all the pressurization fluid 45 initially contained in the storage tank 50 has been used.

[0149] For example, if the storage tank 50 is a bottle containing the pressurization fluid 45, when the bottle is empty, the robot 10 can be connected to a bottle replacement system 99, schematically represented in [Fig.4]

[0150] The bottle replacement system 99 is, for example, operated manually by an operator on site.

[0151] The fluidic circuit 55 then connects the storage tank 50 to the internal volume 25 in a sealed manner, through the external casing 20.

[0152] The configuration of the storage tank 50 (inside or outside the outer casing 20) is independent of the other characteristics of the first and second embodiments, and all technically feasible combinations between the first and second embodiments are conceivable.

[0153] In order to guarantee the safety of the pressurization system 40 and its proper functioning, one or more pressure relief systems may be provided on the robot 10.

[0154] Examples of pressure relief systems will now be described with reference to Figures 3 and 4.

[0155] The robot 10 preferably includes fluidic elements ensuring safety functions of the robot 10.

[0156] The robot 10 includes, for example, a first pressure relief system 82 comprising a safety valve 83 configured to protect the storage tank 50, i.e. to allow pressurization fluid 45 contained in the storage tank 50 to escape outside the outer casing 20 of the robot 10.

[0157] The safety valve 83 is used, for example, when the robot 10 is subjected to sharp increases in temperature, for example during a fire or abnormal heating, and / or sharp increases in pressure.

[0158] For example, when the pressure of the pressurizing fluid 45 in the fluidic circuit 55 and / or in the storage tank 50 reaches a value greater than or equal to, for example, 200 bar, the valve 83 opens to allow pressurizing fluid 45 to escape to the outside in order to control the pressure in the storage tank 50.

[0159] The first pressure relief system 82 also includes a first valve 84 and a control valve 85.

[0160] Valves 84 and 85 are used for example when the user wishes to carry out a voluntary depressurization to perform maintenance actions for example.

[0161] For this purpose, the valves 84 and 85 are manually controlled by an operator who receives information on the pressure measured inside the storage tank 50 by the second pressure sensor 80.

[0162] Advantageously, downstream of the control valve 85, an outlet nozzle 86 is arranged to guide and evacuate the pressurization fluid 45 outside of the outer casing 20.

[0163] In the same way as before, the robot 10 includes for example a second pressure relief system 88 of the internal volume 25 of the robot 10.

[0164] The second pressure relief system 88 is an automatic control mode comprising a set of isolation valves.

[0165] In order to have a second robust pressure relief system 88 of the internal volume 25, the robot 10 includes for example a system of nested and / or stacked isolation valves.

[0166] Pressure relief within the internal volume 25 of the robot 10 may be necessary, for example, when a change in atmospheric temperature is measured.

[0167] For this purpose, the robot 10 includes a first pressure relief valve 89.

[0168] This first pressure relief valve 89 is arranged to be opened in normal operation and to trap a quantity of fluid 45 in a pressure relief storage space 92.

[0169] The first pressure relief valve 89 is for example motorized and controlled by the electrical control unit 72 according to a measurement signal from the first pressure sensor 75 representative of the pressure in the internal volume 25.

[0170] When a pressure threshold is measured by the first pressure sensor 75 in the internal volume 25, the pressure relief valve 89 is closed by the electrical control unit 72 in order to fluidly isolate the pressure relief storage space 92 containing a quantity of pressurizing fluid 45 under pressure from the internal volume 25.

[0171] Then, a second pressure relief valve 95, fluidly connected to the pressure relief storage space 92, opens to release the quantity of pressurizing fluid 45 trapped in the pressure relief storage space 92 out of the outer casing 20 of the robot 10.

[0172] The second pressure relief valve 95 is, for example, also motorized (in the closed position by default) and controlled by the electrical control unit 72 according to a measurement signal from the first pressure sensor 75, and / or according to the configuration of the first pressure relief valve 89.

[0173] The second pressure relief valve 95 is arranged to transfer the quantity of pressurization fluid 45 trapped in the pressure relief storage space 92 outside the outer casing 20.

[0174] Optionally, a check valve 96 is arranged between the first and second pressure relief valves 89, 95, and in particular between the pressure relief storage space 92 and near the second depressurization valve 95 as shown in [Fig.3] and 4.

[0175] The presence of the valve 96 prevents unwanted air from entering the internal volume 25 from outside the robot 10.

[0176] Optionally, a filter or strainer 97 is added downstream of the second pressure relief valve 95 to prevent the entry of particles, moisture and / or insects inside the robot 10.

[0177] Since the outer casing 20 is not perfectly sealed, leaks of pressurization fluid 45 occur continuously. The pressurization system 40 is further configured to compensate for these leaks and maintain the internal volume 25 of the robot 10 under positive pressure, in particular based on the pressure measurement provided by the first pressure sensor 75.

[0178] Thus, the leaks of pressurization fluid 45 ensure the renewal of the pressurization fluid 45 inside the internal volume 25 and also ensure that the entire internal volume 25 is pressurized with the pressurization fluid 45.

[0179] A method for pressurizing the internal volume 25 of a robot 10 will now be described, with reference to the embodiments described in Figures 1 to 4.

[0180] For the first filling or filling after maintenance of the robot, a preliminary step to be implemented by an operator consists in particular of purging the robot 10, to replace the surrounding air with the pressurization fluid 45.

[0181] Common to the various embodiments, the pressurization process includes a first step of storing the pressurization fluid 45 in liquid form in a storage tank 50 mounted on the robot 10, followed by a step of injecting a quantity of pressurization fluid 45 from the storage tank 50 into the internal volume 25 of the robot 10, the injected pressurization fluid 45 passing in the gaseous state, to maintain pressurization of the internal volume 25 of the robot 10.

[0182] Preferably, the step of injecting the pressurization fluid 45 is carried out sequentially by transferring the quantity of fluid 45 from the storage tank 50 to the calibrated storage space 60 and then by injecting the quantity of pressurization fluid 45 contained in the calibrated storage space 60 into the internal volume 25.

[0183] In an example implemented with a robot 10 such as that illustrated in [Fig.3], the injection step is divided into two sub-steps.

[0184] A first substep includes opening the isolation valve 70 (normally closed) and the first and second ways 65A, 65B of the injection valve 65, in order to transfer pressurization fluid 45 from the storage tank 50 until the calibrated storage space 60 is filled.

[0185] Once the calibrated storage space 60 is filled with pressurizing fluid 45, the isolation valve 70 (normally closed) is closed.

[0186] The second and third ways 65B, 65C of the injection valve 65 are then opened in order to inject the pressurization fluid 45 from the calibrated storage space 60 into the internal volume 25.

[0187] If necessary, the pressurization fluid 45 at the outlet of the injection valve 65 is guided by a conduit to the slowing system 78 where its change of state from liquid to gaseous is slowed down in order to compensate for thermal losses.

[0188] Furthermore, in an example implemented with a robot 10 as illustrated in [Fig.4], comprising a simple injection valve 65 and a calibrated storage space 60 defined in the fluidic circuit 55 upstream of the injection valve 65, the pressurization process of the internal volume 25 of the robot 10 differs from that of the first mode implemented by the injection substeps.

[0189] A first substep includes opening the isolation valve 70 until the calibrated storage space 60 is filled, and then closing the isolation valve 70 once the calibrated storage space 60 is filled with pressurization fluid 45.

[0190] A second substep includes opening the injection valve 65 in order to inject the pressurization fluid 45 from the calibrated storage space 60 into the internal volume 25.

[0191] The pressurization system according to the invention has many advantages.

[0192] First, since the storage tank 50 for the pressurization fluid 45 is configured to store the pressurization fluid 45 in a liquid state, the robot's autonomy can be greater and more adaptable.

[0193] Indeed, the quantity of pressurization fluid 45 stored in liquid form is greater, for a given volume, than the quantity of pressurization fluid 45 stored in gaseous form.

[0194] Thus, the robot 10 needs to be recharged with pressurization fluid 45 for the pressurization of the internal volume 25 less frequently and can operate longer autonomously while being able to operate in areas at risk of explosion.

[0195] Furthermore, when the pressurization fluid 45 is carbon dioxide, it is easy to obtain carbon dioxide from any industrial site in order to recharge the storage tank 50 of the robot 10.

[0196] Moreover, at room temperature carbon dioxide is in liquid phase at a lower pressure than other fluids, and therefore more easily accessible.

[0197] Indeed, carbon dioxide is a gas readily found in industry, particularly in carbon dioxide fire extinguishers, which are widely used for firefighting purposes.

[0198] The presence of a calibrated intermediate storage space 60 of the pressurization fluid 45 in the fluidic circuit makes it possible to simplify the fluidic circuit 55 which does not need to provide a system for measuring the quantity of pressurization fluid 45 injected into the internal volume 25 in order to control the pressure in the internal volume 25 of the robot 10.

[0199] The injection valves 65 and isolation valves 70 are advantageously combined in order to regulate the circulation of the pressurization fluid 45 in the fluidic circuit 55 and to inject, sequentially, the pressurization fluid 45 into the internal volume 25.

[0200] The presence of two valves makes it possible in particular to decouple the regulation and injection functions of the pressurization fluid 45 and limits in particular incidents related to human handling error or a control fault from the electrical control unit 72.

[0201] Another advantage of the invention is the simplification of the design of the refueling stations (electrical refueling and pressurization fluid refueling). Indeed, by implementing fewer pressurization fluid refueling points, a majority of refueling stations can be equipped with electricity only, and therefore require less frequent distribution across the site than when they were combined with gas refueling points.

[0202] This advantage makes it possible in particular to use electrical charging stations by induction (without physical contact), which simplifies the design and operation of electrical charging of the robot, in particular because there is no precise physical contact to ensure between the electrical charging station and the robot.

[0203] It might then be possible to converge towards a universal electric charging station, whereas today each robot has a personalized charging station depending in particular on its unique geometric shape.

[0204] More generally, the pressurization system is capable of maintaining the internal volume of a moving mechanism under positive pressure, in order to ensure proper operation of the mobile mechanism in areas with potentially explosive atmospheres.

[0205] In other words, the pressurization system is not limited to the internal volume of a robot, but can be used for any other conceivable moving mechanism.

Claims

Demands

1. Pressurization system (40) of a mobile mechanism, in particular a robot (10), the mobile mechanism comprising a body (15) including an outer shell (20) defining an internal volume (25), the pressurization system (40) being mounted on the mobile mechanism and configured to maintain a pressurization fluid (45) under pressure in the gaseous state in the internal volume (25), the pressurization system (40) comprising a storage tank (50) of the fluid and a fluidic circuit (55) fluidically connecting the storage tank (50) to the internal volume (25) to inject a quantity of pressurization fluid (45) from the storage tank (50) into the internal volume (25), characterized in that the pressurization fluid (45) is stored in the storage tank (50) in the liquid state, the pressurization fluid (45) passing into the gaseous state when injected into the internal volume (25).

2. Pressurization system (40) according to claim 1, wherein the pressurization fluid (45) is a dry fluid and is selected from carbon dioxide, halogenated gases or a mixture thereof.

3. Pressurization system (40) according to claim 1 or 2, wherein the fluidic circuit (55) comprises a calibrated fluid storage space (60), the fluidic circuit (55) being configured to sequentially transfer pressurization fluid (45) in liquid form from the storage tank (50) to the calibrated storage space (60) and then transfer the pressurization fluid (45) from the calibrated storage space (60) to the internal volume (25).

4. Pressurization system (40) according to claim 3, wherein the calibrated storage space (60) is sequentially fluidly isolated from the internal volume (25) of the moving mechanism during the transfer of the pressurization fluid (45) in the liquid state from the storage tank (50) to the calibrated storage space (60), and fluidly isolated from the storage tank (50) during the transfer of the pressurization fluid (45) from the calibrated storage space (60) to the internal volume (25).

5. Pressurization system (40) according to claim 3, wherein the fluidic circuit (55) includes an injection valve (65) arranged fluidically between the calibrated storage space (60) and the internal volume (25) to control the circulation of the pressurization fluid (45) from the calibrated storage space (60) to the internal volume (25).

6. Pressurization system (40) according to claim 5, wherein the injection valve (65) is a three-way valve (65A, 65B, 65C) comprising a first position for fluidly connecting the storage tank (50) to the calibrated storage space (60) to fill the calibrated storage space (60) with pressurization fluid (45) and a second position for fluidly connecting the calibrated storage space (60) to the internal volume (25) to inject the pressurization fluid (45) into the internal volume (25).

7. Pressurization system (40) according to claim 5, wherein the injection valve (65) is a simple valve, the calibrated storage space (60) being defined in the fluidic circuit (55) upstream of the injection valve (65), the closing of the injection valve (65) fluidly isolating the calibrated storage space (60) from the internal volume (25), the opening of the injection valve (65) fluidly connecting the calibrated storage space (60) to the internal volume (25) for the injection of the pressurization fluid (45) into the internal volume (25).

8. Pressurization system (40) according to any one of claims 3 to 7, wherein the fluidic circuit (55) includes a normally closed isolation valve (70), located upstream of the normally closed injection valve (65).

9. Pressurization system (40) according to claims 7 and 8, wherein the calibrated storage space (60) is defined between the isolation valve (70) and the injection valve (65).

10. Pressurization system (40) according to claim 8 or 9, wherein the isolation valve (70) is controlled according to a measurement signal from a first pressure sensor (75) representative of the pressure inside the internal volume (25), in order to secure the internal volume (25) of the moving mechanism, and the injection valve (65) is controlled according to the opening and closing of the isolation valve (70).

11. Pressurization system (40) according to any one of the preceding claims, comprising a second pressure sensor (80) arranged to measure the pressure inside the storage tank (50).

12. Pressurization system (40) according to any one of the preceding claims in which the fluidic circuit (55) includes a system for slowing down (78) the expansion of the pressurization fluid (45) injected into the internal volume (25).

13. A method for pressurizing the internal volume (25) of a mobile mechanism such as a robot (10), the pressurization method comprising the steps of: - storing a pressurization fluid (45) in a liquid state in a storage tank (50) mounted on the mobile mechanism, - injecting a quantity of pressurization fluid (45) from the storage tank (50) into the internal volume (25) of the mobile mechanism, the injected pressurization fluid (45) passing from a liquid state to a gaseous state, to maintain a pressurization of the internal volume (25) of the mobile mechanism using the pressurization fluid (45).

14. A method according to claim 13, wherein the pressurizing fluid (45) is dry and is selected from carbon dioxide, halogenated gases, or a mixture thereof.

15. A method according to claim 13 or 14, wherein the injection step is carried out sequentially by transferring the quantity of pressurizing fluid (45) from the storage tank (50) to a storage space (60) and then injecting the quantity of pressurizing fluid (45) contained in the calibrated storage space (60) into the internal volume (25).

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