FR2550830A1 - Remote electrical and independent control of hydraulic systems in an explosive atmosphere - Google Patents

Abstract

The invention relates to systems making use, in order to ensure the indirect or direct control of a device for distributing pressurised hydraulic fluid, of an electrical or mechanical actuator complying with safety standards: use in explosive atmosphere, intrinsic safety. The generator stage 1 provides the power supply, control, data and electrical monitoring functions. The actuator 2 driven by an electric micro-motor 3 provides the control of the hydraulic distributor 4 to which it is directly coupled in order to obtain, if required, the progressive, proportional or slaved control of the power receiver 5. The hydraulic distributor 4 provides, directly or relayed, the control of a power receiver 5. The components and electrical connections 6, separately or in association, comply with the intrinsic safety standards. The independent formula can be associated with all networks and with all automatic control systems. This control, separating the stages of the system and complying with the safety standards, allows its use in an explosive atmosphere, in mines, on moving supports, in gassy or aggressive atmospheres, with thin fluids and in offshore or refinery installations, in a "petroleum" atmosphere for example.

Description

 Hydraulic techniques make it possible, in addition to the possibilities of transforming, transporting and using the necessary energy at specific points of the machines, to carry out the remote control, to master and control the behavior of the receivers concerned, hydraulic cylinders , by ashing linear movements, or hydraulic motors, generating rotary movements, for example.

 The remote control of hydraulic receivers calls upon different needs and technical possibilities to different types of transmission and different categories of energy, for example; remote transmission using the hydraulic fluid of the system as pilot fluid operating small cylinders or small hydraulic motors; remote transmission using an auxiliary circuit using compressed air operating pilot components of pneumatic technique, under conditions similar to the formula using the hydraulic fluid of the system; remote transmission using electrical energy, activating solenoids, all or nothing technique, directly operating the valves or the drawer of the hydraulic component of the pilot stages or power of the system, or proportional technique, operating in this case the hydraulic components according to the laws governing the electric controlled floor.

 Some operations cannot accommodate equipment using technical cases and therefore cannot allow the use of standard components, widely distributed, but having drawbacks and even fundamental impossibilities, or, for example, for reasons of distance, size, vulnerability or even geometry and shape of the movements concerned, in the case of remote control using hydraulic or pneumatic fluids as a means of transmission; either for safety reasons, where the remote control uses electrical energy to ensure the transmission of orders and operate the hydraulic components of the system, in the case where the technique and the production of the equipment does not meet the norms imposed on the operating sites of the machine concerned, in explosive atmospheres, in gassy mines or in the petroleum industries, in refineries, on platforms or on tankers, for example.

The present invention relates to the remote and autonomous electrical control of hydraulic systems in an explosiblo atmosphere, using for the stages generation, connection and transformation of the order, electrical energy, within the framework of the techniques known as intrinsic safety and meeting the imposed standards. by classification bodies and giving rise to approval, in accordance with standard cases; for memory: Standards UTE-NF-C 23.514, General rules and UTE-NF
C 23.520, Intrinsic Security "I", the citation of these standards not having a limiting nature, as regards the invention; the present text is not intended to set the limits of requests and approvals relating thereto.

 In addition to the priority nature of the safety parameters and compliance with standards, the main guiding ideas sui @@ antes presided over the prior study of the remote and autonomous electrical control of hydraulic systems in explosive atmospheres, object of the present invention.

 Create assemblies with an autonomous character, particularly with regard to the generation stages and the electrical control station, the only formula that ensures control of the energy source and its use, within the framework of safety standards , and moreover avoiding making "run" electric cables over great distances, in areas impossible to oversteer and to guarantee, in mines, in sizes with walking supports, for example.

 The autonomy of the generation and electrical control station stages may, depending on the type of machine and the type of operation on site, concern each hydraulic system or concern a family of hydraulic systems relating to the same machine, on a walking support used in a pruning, in gassy mine, for example.

 The hydraulic stages, pilot and power, can normally call on collective hydraulic controls, only the parameters of fluid, filtration, pressure and flow, having to be respected according to the components used.

 Avoid creating a universal material, abnormally efficient, but a material intended to solve the specific problems posed by machines and machines intended for industry, mines and offshore marine, for example, where the need is bad or incompletely satisfied.

 Avoid asking this equipment to perform out of proportion response time performance, with all-or-nothing technical functions, the aim of this invention, in its first applications, the proportional and enslaved technical functions possibly being studied and subsequent achievements.

 Avoid creating new components, especially with regard to the generator stages, electric control station and electric motor, system control receiver whose performance and reliability should be demonstrated, but use or adapt, as far as possible. possible, known and diffuse components in industry, marine and aeronautics, presenting all guarantees of quality, safety and reliability, and meeting the standards governing the use in the envisaged operating environments.

 This approach makes it possible to master homogeneous assemblies, remaining acquired, that in all cases, and regardless of the characteristics of each component, each family of components constituting an electric and autonomous remote control of hydraulic systems in an explosive atmosphere, must satisfy controls, recipes and approvals imposed by standards.

 This invention relates to a hydraulic component with electric remote control, designated by the term electric and autonomous remote control of hydraulic systems in explosive atmosphere allowing, for example, connected directly to a cylinder or to a hydraulic motor, to ensure the circuits of the fluid of work, flange or connected to a hydraulic component to ensure its hydraulic control, associated with a hydraulic, mechanical, pneumatic or electric component to ensure its control, direct or indirect.

 By way of example, to simplify the texts and the plates imagining the remote electric and autonomous control of hydraulic systems in explosive atmosphere, object of the present invention, we will retain only one type of resolution relating to the Electro-Hydraulic control of 'a walking retaining rinse * used in mina, application corresponding perfectly to safety requirements and accreditation standards, falling into the Intrinsic Safety category, standard NF-C- 23.520.

 Figure 1, presented in the form of a block diagram, image. A type of remote control chain.

 Figure 2, image, by way of example, a type of drawer technique distributor, accumulated with a piloted check valve.

 FIG. 3, associated with FIG. 2, makes it possible to analyze the hydraulic circuits of the distributor.

 FIG. 4 represents the hydraulic diagram of a component grouping the subassemblies described by the preceding figures.

 Figure 5, with the schematic representation of Figure 4, simplified to be incorporated into a general diagram.

 Figure 6, presents a typical diagram comprising distant cammands, applied to a walking support used in gray mine.

FIG. 1, image, by way of example, in the form of a block diagram, a type of remote and autonomous electrical control chain of hydraulic systems in an explosive atmosphere.

An autonomous assembly, following the chain imagined by fi gura 1, is composed of the following main subsets:
A generator stage [1], an actuator stage [2], an electrical connection [3], between the generator [1] and the neur action [2], a hydraulic control or power distribution stage [4], ensuring, according to the type of diagram retained, the supply of hydraulic fluid to the receiver.

Each subset, according to FIG. 1, and still, by way of example, can be made up of the following components:
The generator stage [1] groups the electric current generator C53, of accumulator technique, for example, and the electrical command and safety station [6], comprising, inter alia, the command contactors, the electrical safety valves and function and fault detection, the decoupling system for the replacement on the site of the generator stage, for recharging or overhaul, the generator stage [1] considered as one of the determining elements of the safety concept , having to respond, in all cases and whatever the variant of the scheme adopted, to the standards and approval recipes governing safety in a explo Bible atmosphere,
The actuator stage [2] is made up of components intended to transform the rotational movement of the electric motor [7] in las sans + and - into a linear control movement of the hydraulic stage.

 The electric motor [7] is, controlled from the control and safety station [6], drives, in rotation the reduction gear C8) by the play of the coupling (9); in case conditions, depending on the choice of synthesis reducer [8] the Mechanical transformer [10] of screw-nut technique, for example, transforms, on the one hand, the rotary movement of output of the synthesis reducer [8] into a linear movement movement; on the other hand adjusts, according to the characteristics of the synthesis reduction system [8] and the mechanical transformer [10], the time and effort parameters to the characteristics required by the hydraulic control or power stage [4].

 Like the generator stage [1], the electric motor [7] must meet the standards and approval recipes governing safety in potentially explosive atmospheres.

 The electrical connection [3] provides the electrical connections between the generator [1] and the actuator [2], this connection provides the commands transmitted by the electrical control and safety station [6] and return, checks on the operation in progress and safety-related information.

 Like the generator stages [1] and the electric motor [7] of the actuator stage [2], this connection must meet the standards and approval recipes governing safety in potentially explosive atmospheres.

 A generator stage (1) can, depending on the type of hydroelectric scheme and according to the operating machine, provide the functions of a soul or of several actuators.

 hydraulic control or power distribution stage [4], is shown by way of example, in FIG. 1, in the schematic form of a 3-way type slide valve distributor [11], this distributor can be indifferently all-or-nothing or proportional, drawer, flap, linear or rotary or even mixed ice dispenser technique.

 In all cases, the actuator [2] must, by construction, be adapted to the distribution technique considered, in particular with regard to the time base parameters, value of the mechanical control force and form of the linear control. , according to the example cited, rotary, or of tech niquo with cams, for example.

 To complete this overview, three examples of receiver control, the single-acting cylinder [12], according to FIG. 1 have been imagined; direct control, the hydraulic distributor [4] directly performs the functions of the jack [12]; stepped control by using a hydraulic distributor of lais [13], hydraulically controlled by the pilot distributor [4], ensures the functions of the hydraulic cylinder 12, in the event of flow or pressure incompatible with the hy stage pilot hydraulics [4], associated with the actuator [2]; or alternatively, the hydraulic relay distributor is replaced by a hydraulically controlled non-return valve [14] especially in cases where absolute sealing of the cylinder circuit [12] is required.

 In order to facilitate the study and analysis of the hydraulic circuits, the distribution orifices have been identified; port P, connected to the general circuit, fluid under pressure; orifice R, connected to the general return circuit, pressure sense fluid; port a, connected to the function circuit, port b, fluid supply to jack 12.

 Figure Z, shown for the record, uses conventional elements used in the construction of components for the hydraulic distribution of pressurized fluid, intended to perform the functions of receivers, of actuators or hydraulic motors technique, or the control of hydraulic stages relay, for example.

 By way of example the hydraulic distributor [11] represented by FIG. 2; intended, in principle, for the equipment of mine mine retaining supports satisfies the characteristics of such machines, safety fluid of Engler viscosity, operating pressure 300-450 bars, long-lasting resistance to absolute tightness, 9years talk about the low lubrication and aggressive characteristics of the fluid and the atmosphere; uses the combination of stacked drawers and non-return valves.

 In addition, for example and information, it should be specified that the choice of materials, and functional clearances must satisfy very high yields, compared with the power factors allowed, within the framework of the standards imposed.

 FIG. 2, image, by way of example, a hydraulic distributor [11], possibly usable for the hydraulic control of mine walking supports, associated with the actuator stage C2J, described in FIG. 1.

 The hydraulic distributor [11] described by way of example has the following construction and service characteristics.

 A body [15], comprising the bores, the chambers, the cells and the necessary distribution channels, allows the displacement of a distribution drawer [16] equipped at its end with a non-return valve [17].

 The body [15] includes balancing chambers, compensated by the resulting effort, depending on the sections of the outgoing rods, in the open air [18] and [19].

 The orifice [20], marked P, is re-attached to the general grid, under pressure; the orifice [21], identified, a, is reconnected to the function, piloting circuit, of a power distributor with hydraulic piloting [13] of a non-return valve with hydraulic piloting [14] ensuring the functions of a hydraulic cylinder [12], or directly to the hydraulic cylinder [12], according to the three cases treated by way of example in FIG. 1; the orifice [22], marked R, is connected to the general return of the network.

 The channel [23], between the chamber [24] and the chamber [25] ensures the hydraulic balancing of the drawer [16], regardless of its position and its function.

 The channel [26] allows, depending on the position of the slide, to channel the fluid under pressure orifice C20) towards the distribution orifice [21].

 The yoke [27] ensures the coupling of the hydraulic distributor [11] to the actuator [2].

 The representation shown in Figure 2 relates to a distributor in position, called neutral, the pressurized fluid arrives through the orifice [20], marked P, in the chamber [24], the check valve [17] mechanically blocked and hydraulically confirmed on its seat, guaranteed watertightness and prevents the passage of fluid through the channel [26], moreover the distribution slide [16] does not offer any possibility of passage and blocks the groove [29] confirming, if necessary, the sealing of the supply pressure circuit, the orifice [21], marked a, connected to the function circuit and connected to the orifice [22], marked R, connected to the general return circuit, by the play of the groove [28] in the drawer [16]; in conclusion the supply pressure is blocked, the function circuit is connected to the general return circuit, therefore without action.

@ Figure 3 image the hydraulic distributor C11) operated by the actuator [2] which has made a tensile force on the slide [16] via the yoke [27] which is coupled to it.

 This representation relates to a distributor in said position, function, the whole of the drawer [16] equipped with its non-return valve [17], has been moved by n / millimeters, the non-return valve [17] is no longer pressing on its seat, the groove [28] of the drawer [16] connects the orifice [21], marked a, at the groove [29], the following circuits are thus established; the orifice [20], marked P, is connected to the @ channel [26] which is itself connected to the orifice (21) marked a, connected to the function circuit, the feed fluid and operates the recoptor [12], ie via the relay stage [13] or [14] or directly, under the conditions; analyzed by Figure t.

 In conclusion, the supply pressure activates, directly or indirectly the receiver, the hydraulic cylinder [12], for example; the orifice [22], marked R is isolated by the drawer C163 without groove in this area.

 FIG. 4 image the schematic representation of a set of associated components and of one-piece presentation, of bored block technique with mounting in baseplate.

 This assembly groups the actuator [2], the hydraulic distributor [11] and the hydraulically controlled non-return valve (14), follow the direct control diagram of the jack [12], analyzed by FIG. 1, in the cases where absolute tightness of the actuator circuit [12] is required, for example.

 FIG. 4 shows the location of the orifices P, R and a and of the electrical connection [3] under conditions identical to those of FIGS. 1, 2 and 3.

 This representation, of traditional form, must be simplified, so as not to clutter a hydraulic or electrical diagram of a complete machine comprising many components.

 FIG. 5 image a simplified diagram whose representation will be retained by the diagrams of elements or assembly of machines, in particular on the diagram, FIG. 6, of this presentation.

 This representation no longer includes the references of the elementary components, the assembly designated under the term, check valve hydraulically piloted by an electro-mechanical safety actuator, (30) is to be considered as a component, in its own right, at the same as a pump. hydraulic or a servo valve also made up of multiple elements.

 Only the identification of the orifices P, R and a, and of the electrical connection [3], are maintanus by this schematic representation, reference cases being essential for the reading of the hydraulic and electrical diagrams.

 FIG. 6, present @, by way of example, the partial electro-hydraulic diagram of a walking support used in a gassy mine size, in an explosive atmosphere.

 This diagram uses remote and autonomous electrical control of hydraulic systems in explosive atmospheres, object of the present invention, for the control, in displacement, in power and in t @ nue, of support props, in valves of non return hydraulically piloted by an electro-mechanical safety actuator [30], described by way of example in FIGS. [4 and 5], and schematized, according to FIG. 5.

 A walking support consists of several hydraulic jacks holding the roof of the mine, known as props; to simplify the diagram, only one of them has been shown.

 The diagram, presented by way of example, in FIG. 6, uses simple non-return valves, in order to facilitate the analysis of the functions, it being understood that this formula has only demonstration value, the production of components that can call, as necessary, security and procedural requirements, without neglecting the factories reliability and price, the hydraulic techniques best suited.

 The diagram in FIG. 6 only deals with the props, determining on a walking support, the functions of displacement, shifting, pitching etc ... can of course be treated according to the same techniques by calling on compos @ identical, neighboring or adapted.

 The diagram, figure 6, applied to mine retaining walls has only value of example, the remote and autonomous electric control of hydraulic systems in explosive atmosphere, as specified on various occasions by the present presentation, is intended to be used everywhere and on all machines and machines where the concept of safety is decisive.

 In the same spirit, the concept of system autonomy concerns the most difficult cases to treat, often without an industrial solution to date, of course from the source of information and the order post. make use of techniques of partial or relative autonomy, rescue, breakdown assistance or temporary or occasional security or even be associated with traditional assemblies.

 The diagram @ hydraulic with electric control, represented by way of example by figure 6 is intended for the specialist hydraulics, this diagram @ of traditional representation parmet the analysis of the functions of the operations and the movements of a prop.

 For the record, this diagram also includes non-return valves piloted by an electro-mechanical safety actuator [30] and a jack [31] of the double-effect prop type comprising the orifices marked b, bottom section and c, section ring, a filter [32] of the pilot circuit, a safety valve [33] between the cylinder [12] and the non-return valves [30] of the circuit and a pressure gauge [34].

 The remote electrical control is operated from the station [1] connected to the distributor [30] of the system by the electrical connection [3].

 On the other hand, the pipes shown in the diagram in Figure 6 have been identified, in order to facilitate reading, pressure piping, general network [35], general return pipeline [36] can @ lization of return-drainage from pilot circuit C373 and pilot circuit pipe [38].

 In conclusion of these descriptions, quoted only by way of example, it should be clarified that the autonomous nature of this remote command does not have a limiting character, and on the contrary corresponds to a technical difficulty, guaranteed without delay. use of the control in the most difficult CAD, does not exclude the possibility of having recourse to a generator stage [1] grouping the source of generation of electric current [5] and the control and security station [ 6] having their origins from the general network and also from replacing the command and security station [6] by a collective station, possibly connected and controlled by a programmed system.

 On the other hand, it must be confirmed that the techniques and their schematic applications cited by way of example are not limiting in nature, the actuator stage [2] being able to unreservedly control hydraulic tech valves or that with a slide valve, with vanes, valves or E nozzles, for example separately, or associated.

Claims (6)

 I) Remote electrical control of hydraulic systems in an explosive atmosphere characterized by - A generator stage (1) group an electric current generator t53 an electric control station C6) comprising the safety and fault detection devices. - An actuator stage [2] consisting of an electric micro-motor [7] which can rotate in the + or - direction, depending on the selection made at the control station [6], driving directly or via a coupling [9] a mechanical synthesis reducer [8], itself coupled to a mechanical device C103 transforming the rotation of the electric micro-motor couple [7] - synthesis reducer C83, in linear movement, intended to operate the hydraulic stage control or power C43 of the system. These two stages are connected together by electrical connection means (3) equipped with a coupling system. The electrical components and their connections are of safety category in explosive atmosphere.  2) Device according to claim I of autonomous technique characterized in that the electric current generator is a safety accumulator.  3) Oispositif, according to claims I and Z, characterized in that it is supplied with electric current by a general network, separately or associated with other devices according to claims I and 2.  4) Device according to claims 1, 2 and 3, characterized in that its electrical circuits for command, control, detection, faults and power, are connected to a collective station, controlled or not by a programmed system.  5) Device according to claim 4 characterized in that the command is proportional or controlled technique, depending on the law and the selected control mode.  6) Device according to claim 1, characterized in that the hydraulic control or power stage (4) comprises a distribution member [11] of the drawer or valve type.