Fluid guide hose with integrated electrical signal transmission

Abstract

The present invention provides a system comprising a fluid guide hose 5 with power transmission via at least one electrical conductor 8 integrated into a sheath of the fluid guide hose 5 and at least two connection modules 7 on the fluid guide hose 5, wherein fluidic connections and electrical connections 9, 12 of the connection modules 7 can be connected jointly via the fluid guide hose 5, and wherein electrical contact between the connection module and the electrical conductor 8 integrated in the sheath of the fluid guide hose 5 can be established by an electrically conductive cutting element 10 of each connection module 7 penetrating a hose cover 5a. Furthermore, the invention provides a fluid guide hose 5 and a connection module 10 for use in such a system.

Description

Technical area

[0001] The invention relates to a fluid conducting hose (hereinafter often referred to as "hose"), for example a pneumatic or hydraulic hose, according to the preamble of claim 1. In particular, the disclosure relates to a hose in whose wall an electrical conductor is embedded and / or whose wall is reinforced by an embedded electrically conductive fabric, to a use of such a hose, and to the provision thereof.

[0002] Currently, packaging machines and corresponding production lines use pneumatic actuators such as motors, grippers, or pistons to transport or process parts. These actuators are connected fluidically via pneumatic hoses or, alternatively, pipes. Sensors are also often provided to detect, for example, the position of grippers or pistons. These sensors are connected via sensor cables to a controller that controls valves and ultimately also the actuators. Because this controller is often designed as a control block, control valves with connections to the pneumatic lines and electronic control circuits that control these valves and process the sensor data are brought together in these blocks and are thus spatially separated from the actual actuators. Therefore, sensor cables and fluid hoses must be mounted on the control blocks.If decentralized valves are present, additional cables are laid to transmit signals from the control circuits to these decentralized valves.

[0003] However, with the described procedure, space must be provided on the control block for connecting the hoses and cables for the control system and any additional electrical drives, heaters, and the like. Furthermore, space is required for positioning the tools for assembling and disassembling the cables and lines on the control block. Therefore, the control block must be designed relatively large. Furthermore, there is a risk that cables or hoses will be accidentally connected incorrectly. For example, a sensor signal sent through a cable might be present at the wrong input on the control block, or an actuator might undesirably receive signals intended for another actuator.

[0004] A similar design can be used not only for pneumatics with pressures typically below 10 bar or 1 MPa (usually 6 bar or 0.6 MPa), but can also be used for hydraulics. Because the forces required are lower than those often achieved with hydraulics, the hydraulic pressures can also be lower than those usually used for hydraulics, so that one speaks of low-pressure hydraulics. The lower pressures mentioned are below, for example, 100 bar or 10 MPa, preferably in the range between 20 and 40 bar or 2 and 4 MPa. At these pressures, the hoses have to be significantly less stable than conventional hydraulic hoses and pipes, which are usually designed for pressures up to 400 bar or 40 MPa. High-pressure hydraulic hoses are often covered with a stable metal braid to ensure they are more resistant to bursting. Pneumatic systems with pressures typically below 10 bar or 1 MPa (usually 6 bar or0.6 MPa) and the low-pressure hydraulics presented here, however, do not necessarily require such sheathing. Such systems, which are suitable for lower forces, are used, for example, in the packaging industry, where one goal is to keep packaging weights as low as possible. Packaging with easily deformable and movable individual parts is used there, meaning that relatively low forces are required.

[0005] The state of the art includes various fluid guidance systems for transmitting signals and pressures. For example, DE 81 35 428 U1 proposes laying an electrical cable inside a hydraulic line, for example to control solenoid valves in harsh environments such as mining. This allows the use of unreinforced electrical cables housed in standardized hydraulic pressure hoses. The cable connections are then led out of the pressurized fluid at or shortly before the control block and the sensor, valve, or actuator and connected. A mechanical hose coupling also serves as an electrical coupling. A coding pin ensures that various electrical conductors come into contact with the correct counterparts during assembly. These counterparts can then be connected to the control block in the conventional way, for example.

[0006] GB 1 426 622 teaches a signal transmission system for underwater use, particularly in deep-sea drilling rigs. An oil-filled housing with valves controlled by a signal transmission system is to be placed on an underwater drilling rig. An electrical plug for connection to a socket on the housing is connected to electrical cables before the rig is lowered from a ship. The cables run in a pressure line known as the "umbilical," which connects a high-pressure pump on the ship to the hydraulic system underwater. Valves of the high-pressure system in the housing are switched via the electrical lines. The lines are laid next to the pressure line in the umbilical.This publication does not explain how the electrical cables, which are only shown schematically there, are to be arranged in the "umbilical cord" from the ship to the underwater drilling rig, or how the electrical connection and the exit from the "umbilical cord" on the housing are to be made.

[0007] It is the object of the present invention to eliminate or at least mitigate the disadvantages known from the prior art. In particular, therefore, the object of the present invention is to simplify the assembly of components, in particular hoses and cables, on the control block and actuators in conventional manufacturing environments. Furthermore, the risk of incorrect switching due to incorrect cable assembly should be avoided or reduced. Finally, it is desirable to make the system more compact by achieving higher forces with smaller actuator sizes at higher pressures than with pneumatic systems, and by requiring less assembly and installation space on the control blocks. Further objects and advantages of the present invention will become apparent from the following explanation.

[0008] This object is achieved by a generic system comprising a fluid guide hose with power transmission, in particular signal transmission, via at least one electrical conductor integrated in a sheath of the fluid guide hose, and a connection module at each end of the fluid guide hose, wherein fluidic connections and electrical connections can be connected together via the connection modules at each hose end, and wherein an electrical contact between the connection module and the electrical conductor integrated in the sheath of the fluid guide hose can be established by an electrically conductive cutting element of each connection module penetrating a hose cover.

[0009] For the system according to the invention, a fluid guide hose according to the invention is also provided, wherein the at least one electrical conductor is embedded in the fluid guide hose by an extrusion process. The fluid guide hose itself preferably comprises a non-conductive, fluid-tight material into which at least one electrical conductor is embedded. Examples of such non-conductive, fluid-tight materials are rubber, natural rubber, or plastics. Metal wires are preferably used as the electrical conductor. The extrusion process is currently a preferred method for producing hoses in which an electrical conductor is embedded.

[0010] This design allows the hose to be easily connected to the control block and actuator, while simultaneously allowing the sensors on the actuator to send signals via the cable integrated into the hose to the other end of the hose, for example, to a control block. This eliminates the need for multiple cable and hose installations when setting up a system. At the same time, space is saved on the control block for the electrical connections because they are integrated into the fluid connections.

[0011] The invention further provides a connection module for use in a system as described above. The connection module comprises electrically conductive parts and electrically insulating parts. At least one first electrically conductive part is capable of contacting an electrical conductor arranged in a wall of the fluid guide hose by means of an electrically conductive cutting element that can penetrate into the cover of a fluid guide hose. A second electrically conductive part is capable of forming a contact with the first electrically conductive part and of emitting an electrical signal conducted by an electrical conductor for further processing. At the distal end of the connection module, pointing away from the hose end, it can be equipped with a coupling device for coupling to a complementary connection, for example on a control block.An exemplary structural design of a connection module that can be used in the system according to the invention is explained in more detail in the embodiments.

[0012] With such a system, in addition to the fluidic transmission of pressure via the hose and the connection modules, electrical control signals can also be transmitted. If modulated control signals with a typical 24V voltage are transmitted via the hoses, no additional insulation of the exterior of the connection modules is normally required to protect the people working with the system. Only accidental grounding, for example, at the control blocks, needs to be avoided. In this case, the design can be even more cost-effective.

[0013] Advantageous embodiments are claimed in the subclaims and are explained in more detail below.

[0014] In a preferred embodiment, the system comprises at least one control device at one hose end and at least one actuator or sensor at the other hose end, wherein bus communication can be carried out between the control device at one hose end and the actuator or sensor at the other hose end via the electrical conductors in the fluid guide hose. Further preferably, the system is constructed in a star or ring configuration.

[0015] Fluid guide hoses constructed as described above can thus be used for bus communication. By providing signal transmission in the fluid guide hoses, communication protocols can be transmitted. This allows both an electrical and a hydraulic bus system to be constructed using a single connecting element, namely the fluid guide hose discussed above. Thanks to the proposed flexible configuration, it is possible to construct a corresponding bus system in both a star and a ring arrangement. The topology of the fluidic system thus enables the communication protocol to be fed back between actuators, sensors, valves, etc., in order to map different network topologies. This increases the flexibility of the system.

[0016] The fluid guide hose according to the invention can also be equipped with a plurality of electrical conductors between the hose cover and a hose core, wherein the electrical conductors are further preferably made of metal and can each be contacted with at least one electrical connection on a connection module. Currently, metallic conductors are the preferred electrical conductors; in principle, however, conductors based on doped semiconductors or other electrical conductors yet to be developed, such as superconductors, can also be used, provided they can be embedded in a hose sheath. Further preferably, the plurality of electrical conductors in the fluid guide hose are connected to one another in a cable braid. Such a cable braid can be used for power conduction on the one hand and can also reinforce the hose on the other.

[0017] By using multiple electrically insulated conductors, it is possible to transmit multiple sensor signals from sensors at one end of the hose via the hose, as well as to forward control signals from the controller at the other end of the hose to actuators at one end of the hose. For example, control signals can be sent to a valve for switching a double-acting cylinder via two conductive strands, while signals from sensors are received by the controller via one or more further strands. In such a case, however, structural precautions must be taken on the connection module to keep the signals or currents separate there as well, as explained in more detail in the exemplary embodiment. For example, a connection module could comprise a structure made of conductive longitudinal strips that are electrically insulated from one another by other, non-conductive longitudinal strips, for example made of extruded plastic.This makes it possible to transmit comparatively high electrical power in fluid transmission hoses, instead of "only" relatively weak signals along the lines in the hose jacket. The hydraulic oil (or other fluids) in such a fluid transmission hose can also dissipate heat, which is generated by electrical resistance in such lines when they transmit high electrical power.

[0018] In a further embodiment, the fluid guide hose can additionally have an electrically conductive sheath on its exterior. This allows for the transmission of another signal or even a drive current in addition to the embedded electrical conductor, or for signal transmission to occur via both paths and thus with lower electrical resistance. With a sheath that is not made of braiding, and with appropriate thickness, the resistance can be increased not only against bursting but also against bending forces. If the sheath is provided in addition to the cable braid and is insulated from the cable braid, the sheath and embedded electrical conductor should be connectable to mutually insulated electrical connections on the connection module.These two elements allow a closed electrical circuit to be created via the fluid guide hose between the two ends of the hydraulic hose, usually between the control block and the actuator or sensor. Furthermore, it is conceivable to insulate multiple cable braids during production of the fluid guide hose before insertion into a hose extrusion device, for example by coating the individual cables or cable braids with varnish. However, when using this design, care must be taken to ensure that the cutting element of the connection module does not accidentally make contact between the sheath and the embedded electrical conductor. This can be achieved, for example, by removing the sheath in the area surrounding the cutting element, for example by pushing it back using a contact carrier. Burst protection at this point is then ensured by the connection module located there.In this way, you can achieve burst protection for the hose through the cables, while at the same time, signal transmission is achieved through several separate conductors. The corresponding signals can be differentiated and further processed in a control system during reception.

[0019] In a particularly preferred embodiment, the fluid guide hose can be prefabricated in such a way that it can be cut to length at a final assembly location and connected to a connection module for electrical and fluidic connection. The fluid guide hose is designed to be delivered to the assembly site by the meter and to be cut to the desired length from a larger container. Thanks to relatively weak metallic conductors embedded in the hose, no further processing of the hose ends, for example by grinding or the like, is necessary after cutting to length. This simplifies assembly. In contrast, hoses for fluid energy transmission, particularly in the case of hydraulics, are currently prefabricated, i.e.They are cut to a predetermined size in the factory, and then a connection module for hydraulic (or pneumatic) connection to control modules is also added in the factory. At the same time, cables for electrical signal transmission in the systems are also pre-assembled. This results in comparatively high costs for the production of hoses and cables, and with complex hose routing geometries, it is difficult to determine the required hose length in advance.

[0020] As mentioned above, accidental grounding of the connection modules should be avoided. According to a further development, such grounding is prevented by electrical insulation on at least part of the exterior. Especially when higher electrical power and voltages are to be transmitted via the hoses and connection modules, insulating the modules is essential not only to prevent accidental grounding to metallic components, but also to protect the installers and other employees.

[0021] The invention is explained in more detail below with the aid of a drawing. It shows: Fig. 1 a sectional view of a prefabricated hose end from the prior art, Fig. 2 a sectional view to illustrate a connection module according to the invention, which is shown on a hose according to the invention shown continuously, and Fig. 3 a schematic section through a hose into which a (sketched) tip of a contact clamp of a connection module has already penetrated, but does not yet touch the conductors present in the hose.

[0022] The figures are merely schematic in nature and serve only to facilitate understanding of the invention. The same elements are provided with the same reference numerals. Features of the individual embodiments may be interchangeable. They may be used cumulatively or alternatively.

[0023] Fig. Figure 1 is a diagram illustrating a conventional fitting 20 on a hydraulic hose according to the prior art. On the right-hand edge of the figure, a multi-layer hose 21 can be seen, which, from the inside out, has an inner lining 21a, a steel insert 21b for burst protection and stabilization, and an outer sleeve 21c. After cutting to length, the end of the hose 21 must first be reworked to prevent the steel insert 21b from damaging the inner lining 21a or the outer sleeve 21c due to sharp edges that may arise during cutting. Therefore, pre-assembly at the manufacturer's site is required. After such a hose has been cut to the required length and the ends have been machined, the hose is inserted into a (initially undeformed) compression sleeve 30, and a hose nipple 40 is inserted into the hose.In this example, a retaining ring 50 and a union nut 60 are provided on the side of the hose nipple 40 facing away from the hose, which engages a sealing cone 76. The union nut 60 can be screwed onto a counterpart (not shown) and is held in place by a bulge in the hose nipple 40. An O-ring 80 is provided on the side of the hose nipple 40 or fitting 20 facing away from the hose. A retaining ring 50 limits the movement of the union nut 60 on the hose nipple 40 to the side of the hose 21 and at the same time forms a stop for the press sleeve 30. Thus, thanks to the sealing by means of O-ring 80, sealing cone 76 and union nut 60, the prefabricated fluid guide hose 21 can be mounted in a fluid-tight manner on a counterpart (not shown), for example a control block, an actuator such as a piston, a motor or even on a valve or reservoir or the like.

[0024] When assembling the fitting 20, the hose 21 and ferrule 30 are pushed over the hose nipple 40 until they stop at the retaining ring 50. The ferrule 30 is then deformed so that, on the one hand, it penetrates and is held between the retaining ring 50 and a projection on the hose nipple 40, and on the other hand, it clamps the hose onto the sturdy hose nipple 40. By firmly pressing the inner lining 21a onto the hose nipple 40, in particular, a seal can be achieved between the hose nipple 40 and the hose 21. However, care must be taken not to accidentally damage and thereby weaken the hose 21, in order to reliably prevent hydraulic fluid from escaping despite the high pressures in the system. This procedure makes the entire structure of the hose fluid-tight.

[0025] The fitting 20 is connected to a control block, actuator, valve or the like (not shown) by means of the union nut 60.

[0026] Fig. Figure 2 shows a schematic diagram of a fitting 7 according to the invention, which enables the use of the fluid guide hose 5 according to the invention (hereinafter also referred to as “hose”). Fig. 2, the hose 5 is connected to the fitting 7. The fitting 7 is designed in this example as a plug-in fitting and comprises, from the inside to the outside, an (electrically conductive) cable lug 9 as the first electrically conductive part, which is connected to contact pliers 10 as cutting elements and contact points (see also Fig. 3) penetrates into the tube 5 to make contact with the conductor 8.

[0027] At least one conductor or conductive wire 8 is embedded in the hose 5, which can also consist of a wire mesh and can therefore be flat (cf. Fig. 3). The hose 5 is manufactured in a single layer, in other words the conductor 8 is embedded in a matrix during production, for example during extrusion, which forms the hose 5. This matrix is ​​preferably made of plastic and can be divided into a "hose core" 5a on the inside and a "hose cover" 5b on the outside for further explanation. However, the hose core 5a and hose cover 5b are manufactured together and connected to one another, i.e. in a single layer. Therefore, no separation between the two can be seen in the figure. However, the method of manufacturing the hose is irrelevant for the present invention as long as a conductor 8 is embedded or integrated in a non-conductive sheath 5, 5a, 5b.Because such a hose 5 consists largely of plastic and contains only relatively thin metal wires, it can also be very easily cut to length (in contrast to a high-pressure hydraulic hose according to the prior art explained above) and then provided with a fitting 7 without additional processing of the ends.

[0028] The cable lug 9 is inserted during assembly from one side (in the Fig. 2 from the left) is pushed onto the hose between two O-rings 11 and positioned by these O-rings 11. An electrically conductive housing 12 is pushed over the O-rings 11 to create electrical contact with the cable lug 9. An (electrically insulating) housing sleeve 13 is pushed (from the right in the figure) over the conductive housing 12 to abut one of the O-rings 11. At the latest by pushing on the housing sleeve 13, the conductive housing 12 is compressed in such a way that it creates secure electrical contact with the cable lug 9 and at the same time compresses the cable lug 9 in such a way that the contact pliers 10 penetrate the hose cover 5b and come into contact with the conductor 8 in the hose 5. As a result, an electrical signal transmitted via the conductor 8 is reliably transmitted to the housing 12 and can be picked up or forwarded there in a manner known per se.

[0029] As from Fig. 2, the hose 5 is indeed weakened by the penetration of the contact pliers 10, but this occurs at a location where the hose 10 is surrounded by the fitting 7 with its individual parts and is therefore not at risk of leakage or even bursting. Fig. 2 shows a final assembly state of the fitting 7. Depending on the choice of material, in particular for the conductive housing 12 and the housing sleeve 13, both parts can already have the shape shown in the unassembled state or can only be brought into the shown or a comparable shape after assembly, analogous to the prior art, for example by means of a crimping tool or another tool for pressing onto the hose 5, in which the electrical contact between the conductor 8 and the contact tool 10 as well as between the cable lug 9 and the housing 12 is ensured. Although this is Fig. 2 is shown differently, namely with a continuous hose 5 and a non-continuous conductor 8, the hose 5 with the cable lug 9 and the housing sleeve 13 can, for example, also open into a control block, to which the conductive housing 12 is then attached for further processing of the electrical signals.

[0030] Fig. Figure 3 shows a schematic section through the hose 5 at the contact point. Fig. Figure 3 shows a situation in which the schematically illustrated cutting edges of the contact pliers 10 have penetrated the hose, but have not yet touched the conductor 8 in the hose. The contact pliers 10 are indicated here shortly before the point at which they touch the conductor 8. In this schematic view, the contact pliers 10 and conductor 8 are each shown as one-dimensional lines (or as surfaces extending into the hose 5 in the plan view). The key feature of this representation is that the distances between each two of the conductors 8a, 8b, 8c and the lengths of the contact pliers 10 (10a, 10b, 10c) in the circumferential direction are selected such that each contact pliers 10 comes into contact with exactly one of the conductors. If a signal is emitted from each of the three conductors 8a to 8c in the example, these signals are picked up by three contact clamps 10a to 10c, which are then also connected to three (not shown) mutually insulated housing parts 12.The three signals can then be picked up and either determined and forwarded during assembly, or assigned appropriately according to modulation, strength, and the like by a controller into which all three signals are fed. In the latter case, no special care is required during assembly if the control logic automatically assigns the signals to the corresponding channels. With appropriate fittings, which then also internally provide several separate forwarding paths, multiple signals can be forwarded. Alternatively, it is also possible to multiplex several different signals over a single conductor, provided that these signals are encoded differently, for example frequency modulated, fed into the conductor and electrically / electronically separated or filtered from one another at the end or when transferred to further processing.

[0031] Thanks to the simple connection technology shown, a hose can be initially cut to the appropriate length from a larger container during assembly, requiring no reworking of the hose ends. The hose is then fitted with a connection module 5 in the form of a plug-in fitting to enable a leak-free connection to a fluid actuator and, at the same time, an electrical connection. The stiffening of the hose, made of electrical conductors, is simultaneously used to enable communication between an actuator or sensor, which is electrically connected to a corresponding connection module, and a controller. This eliminates the need for additional wiring of an actuator or sensor cable.

[0032] Instead of stiffening, it is sufficient for low pressures, for example, as in Fig.Figure 3 illustrates the routing of only individual conductors 8 within the hose 5. This allows for a hose with smaller bending radii and thus more space-efficient installation. Furthermore, an additional outer sheath (not shown) can further stiffen the hose and increase its burst resistance. Furthermore, if this outer sheath is also electrically conductive, an additional signal can also be transmitted via this sheath through the hose and the connection modules.For this purpose, the connection modules would have to be designed in such a way that they can also transmit the signals transmitted via the electrical conductors embedded in the hose and the signals transmitted via the sheath in an electrically isolated manner from one another, or the signals are fed into only one receiving channel in the connection modules, but modulated according to different communication protocols so that the respective signal receivers can recognize and use the corresponding signal based on the modulation.

[0033] The design shown allows for a reduction in the size of fluid systems. Because the system according to the invention can also be used in bus communication with a ring or star connection and reduces or eliminates the additional use of control cables, such control systems are simpler, more cost-effective, and can be manufactured in a smaller space than conventional systems. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 81 35 428 U1

[0005] GB 1 426 622

[0006]

Claims

[1] System of fluid guide hose (5), characterized by a power transmission, in particular signal transmission, via at least one electrical conductor (8, 8a, 8b, 8c) integrated in a sheath of the fluid guide tube (5), and at least two connection modules (7) on the fluid guide hose (5), characterized by that fluidic connections and electrical connections (9, 12) of the connection modules (7) can be connected together via the fluid guide hose 5, and that an electrical contact between each connection module and the electrical conductor (8, 8a, 8b, 8c) integrated in the sheath of the fluid guide hose (5) can be established by an electrically conductive cutting element (10) of each connection module (7) penetrating into a hose cover (5a). [2] System according to claim 1, characterized byat least one control device at one hose end and at least one actuator or sensor at the other hose end, wherein a bus communication can be carried out between the control device at one hose end and the actuator or sensor at the other hose end via the electrical conductors (8, 8a, 8b, 8c) in the fluid guide hose (5), wherein the system is preferably constructed in a star or ring arrangement. [3] Fluid guide hose (5) for use in a system according to one of claims 1 or 2, characterized by that the at least one electrical conductor (8, 8a, 8b, 8c) was integrated into the sheath of the fluid guide hose (5) by an extrusion process. [4] Fluid guide hose (5) according to claim 3, characterized bya plurality of electrical conductors (8, 8a, 8b, 8c) between the hose cover (5a) and a hose core (5b), wherein the electrical conductors (8, 8a, 8b, 8c) further preferably consist of metal and can each be contacted with at least one electrical connection (4) on a connection module (7). [5] Fluid guide hose (5) according to claim 4, characterized by that the plurality of electrical conductors (8, 8a, 8b, 8c) in the fluid guide hose (5) are connected to one another in a cable braid. [6] Fluid guide hose (5) according to one of claims 3 to 5, characterized by that the fluid guide hose (5) additionally has an electrically conductive sheath on its outside. [7] Fluid guide hose (5) according to claim 6, characterized by that the sheathing is provided in addition to the cable braid and is insulated from the cable braid, both of which can be connected to different electrical connections (12) on the connection module (7). [8] Fluid guide hose (5) according to one of the preceding claims 3 to 7, characterized by that the fluid guide hose (5) can be prefabricated in such a way that it can be cut to length at a final assembly location and connected to a connection module (7) for electrical and fluidic connection. [9] Connection module (7) for use in a system according to one of claims 1 or 2, characterized byin that the connection module (7) comprises electrically conductive parts (9, 12) and electrically insulating parts (13), wherein at least a first electrically conductive part (9) is capable of contacting an electrical conductor (8) arranged in a wall of the fluid guide hose by means of an electrically conductive cutting element (10) which can penetrate into a hose cover (5a) of a fluid guide hose (5), and in that a second electrically conductive part (12) is capable of forming a contact with the first electrically conductive part (9) and of emitting an electrical signal guided by an electrical conductor (8) for further processing. [10] Connection module (7) according to claim 9, characterized by an electrical insulation (13) on at least part of its outer side.

Images