Apparatus for separating gas from a fluid

Abstract

This invention relates to an apparatus for separating gas from a fluid, the apparatus comprising: a container (10) having at least two connecting portions (12, 14) for alternating supply and removal of fluid; and a guiding device (16) that increases the fluid travel for the fluid flow between the connecting portions (12, 14) and causes a reversal of the direction of the corresponding fluid flow. This achieves persistent, and especially automatic, gas separation from the fluid.

Description

Technical Field

[0001] This utility model relates to a device for separating gases from a fluid. Background Technology

[0002] A steering system for a motor vehicle is known from DE102014117327A1, which has:

[0003] A hydraulic cylinder having a piston arranged therein that is movable along the axial direction of the hydraulic cylinder, wherein the hydraulic cylinder has first and second pressure chambers separated from each other by the piston, and the hydraulic cylinder has a first available stroke during operation of the steering system;

[0004] A reversible hydraulic pump, wherein the hydraulic pump is connected to the first pressure chamber of the hydraulic cylinder via a first hydraulic line and to the second pressure chamber of the hydraulic cylinder via a second hydraulic line;

[0005] Oil container for volume compensation of hydraulic cylinders; and

[0006] A device for venting the steering system, wherein the hydraulic cylinder has a second stroke for venting the steering system outside a first available stroke, wherein the device for venting the steering system is configured to fluidly connect the first pressure chamber of the hydraulic cylinder to the second pressure chamber of the hydraulic cylinder when the piston position is in the region of the second stroke of the hydraulic cylinder. Known solutions aim to improve a "closed-center" steering system so that the steering system can be vented simply and reliably, wherein the device for venting the steering system is activated during the filling process of the steering system. For this purpose, it is specified that, for the corresponding steering movement, the piston of the hydraulic cylinder can be adjusted within a range specifically set for the venting pattern of the steering system outside the available stroke of the hydraulic cylinder. The device for venting the steering system is released only in this position of the piston. Utility Model Content

[0007] Based on the prior art, this invention aims to improve known devices for separating gases from fluids, such as air from hydraulic oil.

[0008] Therefore, this invention proposes a device for separating gas from a fluid. The device according to this invention for separating gas from a fluid, such as air from hydraulic oil, has a container with at least two connecting parts for alternating supply and removal of fluid; the device has a guiding device that increases the fluid travel between the connecting parts and causes a reversal of the direction of the corresponding fluid flow. This achieves persistent, and especially automatic, gas separation from the fluid, unlike the prior art which only bleeds the steering system during filling. In particular, it avoids the situation where air inclusions that may appear in the hydraulic oil are no longer simply pushed back and forth during the operation of the hydraulic equipment, but are actively expelled from the hydraulic oil. Accordingly, the hydraulic circuit no longer needs to be pre-vacuum-filled with great care, which is theoretically impossible because a completely air-free space cannot be provided in practice.

[0009] Because the use of a guiding device not only increases the fluid travel for the fluid flow in the container (with the possibility of improved gas separation in this respect), a partial pressure drop also occurs periodically in the area where the direction is reversed by reversal, which helps to improve the precipitation of finely dispersed air bubbles in the hydraulic oil. In addition, smooth flow and eddy formation occur, which promote bubble formation and thus prevent further flow of dispersed air.

[0010] The guiding device is integrated into the container as a gas separator or gas separation device, forming a commercially available structural unit together with the container. This allows the device to be subsequently integrated into existing fluid circuits as a retrofit kit. In this respect, the container with the guiding device as a gas separation device is a largely standardized component, avoiding complex adjustments to the free travel on the hydraulic cylinder for adjusting the steering system or for performing exhaust.

[0011] In a preferred embodiment of the device according to the present invention, the guiding or separating device comprises at least two tubes, preferably two tubes arranged concentrically with each other, wherein the inner tube is placed inside the outer tube and has one free end extending into a connecting portion and the other free end extending into a reversing space surrounded by the other tube, which is configured to be closed in the direction toward the other connecting portion and establish a fluid-guided connection between the reversing space and the interior of the container via the connecting portion. Due to this concentric arrangement, reliable spatial separation from the respective inflow side to the outflow side is achieved, and reliable gas separation of the corresponding fluid flow through the container is achieved due to the flow reversal and the smooth flow through the associated surface abrupt changes.

[0012] Preferably, the inner tube forms a hollow cylindrical guide that passes through the container at one fluid connection point and is fixed to that fluid connection point. Furthermore, preferably, the outer tube forms a hollow cylindrical sleeve with an impact plate on its closed side facing the other connection point, and is closed by the inner tube on its opposite open side, and fixed to the inner wall of the container and / or the inner tube. Preferably, the reversing space is closed by the inner tube, wherein the connection between the reversing space and the interior of the container is located at the height of the relevant end portion. Therefore, while a significant amount of air-containing oil must still be expected on the corresponding inflow side, the air content in the oil decreases as the flow rate of the fluid guide increases towards the corresponding outflow side, resulting in a substantial reduction in gas in the oil. Thus, separation occurs quasi-continuously and automatically during equipment operation.

[0013] In another preferred embodiment of the device according to this invention, the container, fluid connection points, and guiding device are arranged concentrically with respect to their respective longitudinal axes, and viewed axially, the guiding device terminates approximately at the center or below the center of the container in a direction from one fluid connection point toward the other. This results in a structurally simple construction of the device and allows for cost-effective implementation in this regard. This is also beneficial when the container is configured rotationally symmetrically with respect to its longitudinal axis, and particularly when it includes containers common to diaphragm accumulators, which consist of two pressure-sealed shell halves and are typically manufactured in large quantities for mass production.

[0014] What is particularly advantageous here is that, in the two possible fluid flow directions through the container, the flow interruption between the fluid connection points, which would otherwise be directly guided, is achieved by means of a guiding device using flow smoothing and flow reversal, thereby realizing a high separation rate of gas from the fluid in both directions.

[0015] In another preferred embodiment of the device according to this invention, during operation, fluid from the other fluid connection point (inflow side) is degassed by a separating or guiding device, the gas being stored in the upper region of the container. As fluid, having been significantly degassed through the guiding device, is discharged to the other fluid connection point (outflow side), and during a backwashing process involving a volumetric flow reversal between the inflow and outflow sides, the gas accumulated in the container reaches the environment via the other connection point, which is preferably connected to a reservoir of the hydraulic equipment. Thus, effective discharge of gas accumulated in the container is achieved during the container backwashing process. The related separation of gas from the fluid is also referred to in technical terms as defoaming.

[0016] Particularly preferred is the application of the device described above in the scope of hydraulic braking equipment, which is preferably capable of continuous venting, wherein the relevant venting is performed automatically. Even when the hydraulic braking equipment is not used for an extended period, effective venting occurs automatically from the outset. Attached Figure Description

[0017] The apparatus for separating gas from a fluid according to the present invention will now be explained in more detail with reference to the accompanying drawings and embodiments. Here, it is shown in principle and not to scale:

[0018] Figure 1 A longitudinal sectional view of the entire device is shown; and

[0019] Figure 2 The hydraulic circuit diagram is presented in a highly simplified illustration based on... Figure 1 The equipment is designed for applications of hydraulic braking systems. Detailed Implementation

[0020] Figure 1 An apparatus for separating gases from a fluid, such as air from hydraulic oil, is shown. It has a container 10 with at least two connecting portions 12, 14 for alternating supply and removal of fluid. The apparatus also includes a guiding device 16 that increases the possible fluid travel between the connecting portions 12, 14 and causes a corresponding reversal of the fluid flow, as explained in more detail below.

[0021] The guiding device 16 includes two concentrically arranged tubes 18 and 20, wherein the inner tube 18 is vertically oriented into the outer tube 20. Figure 1 Viewed from the direction of observation, the inner tube 18 extends into a connection portion 12 with its lower free end 22 and into a reversing space 26 with its other upper free end 24. The reversing space is surrounded by an outer tube 20, which is configured to be closed in the direction toward another connection portion 14 and otherwise establishes a fluid-guided connection between the reversing space 26 and the interior 30 of the container 10 via the connection portion 28.

[0022] The inner tube 18 is received at its lower free end 22 in a stepped recess 32 within a connecting body 34, which has external threads 36 on its outer periphery in its free end region, and is welded to the underside of the container 10 at its edge, for example, in the form of a circumferential fillet weld 38, which can be exemplarily positioned by means of electron beam welding, laser welding, or resistance welding. Other welding methods may be used.

[0023] The inner tube 18 passes through a through-center opening or container opening 40 on the underside of the container 10 with a radial distance. Furthermore, the inner tube 18 is secured relative to the inside of the outer tube 20 or relative to the cylindrical inside of the connector 34 by means of two retaining rings 42, 44. The connector 34 surrounds a hollow cylindrical central channel 46, which remains constant in diameter and transitions substantially without steps into the correspondingly formed central channel 48 of the inner tube 18, which protrudes beyond the underside of the container 10.

[0024] The connection portion 28 mentioned in the outer fitting 20 includes a plurality of individual through openings 50 in the form of holes, which pass through the column wall of the outer fitting 20 opposite to the longitudinal axis 52 of the device and establish a fluid-guided connection between the reversing space 26 and the interior 30 of the container 10. All through openings 50 (where the portion of the through opening located inside is covered by the inner fitting 18 in the image) lie on a common central plane transverse to the longitudinal axis 52 of the container 10 and have the same free cross-section.

[0025] Generally, the inner tube 18 forms a hollow cylindrical guide that passes through the container 10 at the fluid connection 12 and is fixedly attached to the container 10. In contrast, the outer tube 20 forms a hollow cylindrical sleeve with an impact plate 54 on its closed side facing the other connection 14, and on its opposite open side, the outer tube 20 is closed by the inner tube 18 and otherwise fixed to the outer wall of the inner tube 18 on its bottom side, for example, where a weld (not shown) is applied.

[0026] In an alternative, but also not shown, embodiment, the outer tube 20 is fixed to the inner wall 56 of the container 10 on the bottom side in this region, wherein the central opening 40 is covered by a fluid seal when viewed from the bottom side of the outer tube 20, by means of a weld (not shown) joining the remaining portion of the opening. The flat impact plate 54 extending transversely to the longitudinal axis 52 has the advantage of improving the separation of gas from the fluid flow when the gas-containing fluid flow impacts from the side of another connection 14, for example, because in the region of the impact plate 54, the impacting fluid flow undergoes a sharp reversal, accompanied by the separation of gas and fluid.

[0027] According to Figure 1As illustrated, the aforementioned reversing space 26 has a gradually tapering inner cone 58 arranged on the inside of the outer tube 20, tapering conically towards the impact plate 54. In other respects, the inner cone 58 extends roof-like across the upper free end 24 of the inner tube 18. Furthermore, the outer tube 20, having a constant diameter, surrounds the inner tube 18, and the relevant portion of the reversing space extends through an opening into the connection portion 28, specifically in the region of the stepped, widened portion 59 of the inner tube 18, where the inner tube then directly abuts its outer periphery against the inner periphery of the outer tube 20. In this respect, the reversing space 26 is thus defined by the inner tube 18 and closed towards the connection portion 12. Furthermore, the fluid-guided connection between the aforementioned reversing space 26 and the interior 30 of the container, generated via the connection portion 28, is essentially at the height of the relevant end portion between the outer tube 20 and the inner tube 18.

[0028] In addition, in North Korea Figure 1 Viewed from the direction of observation, container 10 has another connector 60 at its upper end, which is fixedly or fluid-tightly connected to the upper or outer side of container 10 via a fillet weld 62 corresponding to fillet weld 38. This other connector 60 also has external threads 64 at its free end and is centrally passed through a central channel 66, which extends into the interior 30 of container 10 via a stepped widening 67 in the upper side of container 10 and another circular central opening 68. In this respect, container 10, fluid connection portions 12, 14, and guide device 16 are arranged concentrically with respect to the longitudinal axis 52 of the equipment along their respective central axes. Viewed axially, guide device 16 extends from one fluid connection portion 12 toward the other fluid connection portion 14 along its impact plate 54 below the container center 70 into container 10. This arrangement results in particularly good gas separation performance, wherein, in an alternative design (not shown), the impact plate 54 can also be directly inserted along the container center 70. The container 10 is configured rotationally symmetrically with respect to its longitudinal axis 52, and in particular includes a container structure common to diaphragm accumulators, comprising two shell halves 72, 74, which are pressure-sealed together, in particular welded together, along the container center 70. A related diaphragm accumulator shell is exemplarily shown in DE102008062837A1 as having a fiber-wound portion. Diaphragm accumulators are generally manufactured in large quantities, making them particularly cost-effective for use with guiding or separating devices present therein. Furthermore, the pressure vessel construction results in a rigid, high-strength container wall structure.

[0029] Container 10 can be circulated in two directions: from the other connection 14 toward the first connection 12, and vice versa, from the first connection 12 toward the other connection 14. In the first case, the connection 14 forms the so-called inflow side of the device, while the connection 12 forms the outflow side. In the reverse inflow, i.e., when the direction of fluid flow is reversed, the first connection 12 forms the inflow side, and the other connection 14 forms the outflow side. Accordingly, container 10 can be circulated in two possible fluid flow directions, wherein the otherwise directly guided fluid transport between the two connection points 12, 14 is interrupted by means of the guiding device 16, wherein the interruption of transport includes not only smooth flow but also flow reversal. The smooth flow is achieved through the increased distance or surface abruptness of the fluid transport caused by the connection 28, and through the reversing space 26 and the preferred 180° reversal of the fluid flow once the fluid exits from the inner tube 18, is reversibly diverted by the inner cone 58 into another reversing space 26, and then undergoes a further right-angle reversal once the fluid flows out of the reversing space 26 via the through opening 50 of the connection 28 and flows into the relatively larger interior 30 of the container 10. A contrasting reversal occurs in another flow direction, namely from the connection 28 toward the reversing space 26 of the outer tube 20 and further toward the central channel 48 of the inner tube 18.

[0030] During equipment operation, the gas-containing fluid supplied via connection 14 is thus degassed by means of guide device 16, whereby connection 14 constitutes the inflow side of guide device 16, and connection 12 constitutes the outflow side. Here, the impact plate 54 has substantially facilitated the accumulation or storage of gas separated from the fluid in the interior 30 of container 10 or at the upper side of the container. Due to guide device 16, the fluid reaching the outflow side is substantially degassed at fluid connection 12. If, now within the scope of the backwashing process, a volume flow reversal occurs between the inflow and outflow sides such that from now on one connection 12 forms the inflow side and the other connection 14 forms the outflow side, the gas accumulated in the interior 30 of container 30 (which may also be present in the form of foam combined with fluid) is discharged outward via fluid connection 14, and the gas discharged in this way can then be separated from the equipment, as explained in more detail below. However, starting from the impact plate 54 of the outer tube 20, continuous gas separation occurs as the fluid flows further downward toward the connection 28 with the through opening 50, and the same is true in the reverse direction.

[0031] The following explains in detail the basis Figure 1 Gas separation equipment according to Figure 2 Applications of hydraulic braking equipment. Here, Figure 2 A spring-loaded hydraulic brake cylinder 76 is shown, which is fluidly connected to the aforementioned connection portion 12 via a conduit 79 via an adjustable throttle valve or aperture 78. The associated fluid guide extends into the piston side 80 of the brake cylinder 76, which is limited by a piston-rod unit 82. The spring-loaded piston-rod unit 82 extends from the housing of the brake cylinder 76 with its rod component for operating common mechanical brakes. Furthermore, the upper part of the container 10 or another connection portion 14 is connected via a hydraulic connection line 83 to a magnetically actuated two-position three-way valve 84. This two-position three-way valve, in one valve position, establishes a pressure-guided connection between the hydraulic pump 86 and the other connection portion 14 of the container 10, wherein the hydraulic pump 86 supplies fluid from a reservoir 88. For the associated supply to the brake cylinder 76, the valve 84 occupies its position... Figure 2 The switching position on the right is shown in the diagram. A spring-loaded check valve 90 is connected between the hydraulic pump 86 and the valve 84. This check valve opens toward the valve 84 and, in this respect, prevents unwanted backflow of fluid toward the hydraulic pump 86. The associated supply circuit 92 is typically protected via a pressure relief valve 94. The corresponding fluid lines 83, 79 from the valve 84 to the other connection 14 and from the brake cylinder 76 via the throttle valve 78 to one of the connection points 12 are implemented via a common piping system that is conventionally threaded to the external threads 64 and 36 of the connection points 14 or 12.

[0032] When the hydraulic pump 86 is activated, the brake cylinder 76 is actuated, and the piston-rod unit 82 extends against the action of the accumulator, which is in the form of a compression spring 96, to operate the mechanical brake. Figure 2 The guiding or separating device 16, not shown in detail, allows the gas separated in container 10 to accumulate at its upper side towards another connection point 14, which can also occur in the form of foam. If valve 84 is now switched and occupies its position... Figure 2The valve position shown on the left indicates a fluid connection between the interior 30 of container 10 and tank 98, which may also be a component of storage tank 88. In the relevant switching position of valve 84, brake cylinder 76 is no longer subjected to braking pressure from the hydraulic pump 86 side and returns to its unoperated initial position due to the action of compression spring 96, wherein fluid on piston side 80 is pushed out towards another connection 14 via connection 12 and guide device 16. Here, gas or foam stored in container 10 is pushed out of container 10 via valve 84 towards tank 98, which guides ambient pressure, thereby separating the gas from the fluid in tank 98 over a long period. Subsequently, the braking device can be used again for the braking process, wherein quasi-automatic venting can occur even when the braking device has been stopped for an extended period. Accordingly, once the braking process is triggered within the specified range, gas separation occurs in container 10 by means of separation and guide device 16.

[0033] It goes without saying that the application of gas separation equipment in braking equipment is merely exemplary, and the gas separation or splitting equipment can also be reasonably applied to other hydraulic equipment.

Claims

1. An apparatus for separating a gas from a fluid, the apparatus comprising: Container (10), the container having at least two connection points for alternating supply and removal of fluid; A guiding device (16) increases the fluid travel for the fluid flow between the connecting parts and causes a change in the direction of the corresponding fluid flow. The feature is that, in the two fluid flow directions passing through the container (10), the guide device (16) utilizes the smooth flow and flow reversal to interrupt the fluid transport between the connecting parts that would otherwise be directly guided.

2. The apparatus for separating a gas from a fluid of claim 1, wherein, The guiding device (16) includes at least two tubes, wherein the inner tube (18) is placed in the outer tube (20) and has one free end connected to a connection point and the other free end connected to a reversing space (26), the reversing space being surrounded by the outer tube (20), the outer tube being configured to be closed in the direction toward another connection point (14) and to establish a fluid-guided connection between the reversing space (26) and the interior (30) of the container (10) via the connection point (28).

3. The apparatus for separating a gas from a fluid of claim 2, wherein, The inner tube (18) forms a hollow columnar guide body, which passes through the container (10) at a connection point (12) and is fixed to the connection point (12).

4. The apparatus for separating a gas from a fluid according to claim 2 or 3, characterized in that The outer tube (20) forms a hollow cylindrical sleeve body, the sleeve body having an impact plate (54) on its closed side facing the other connection part (14), and the sleeve body being closed and fixed on its opposite open side by the inner tube (18) to the inner wall of the container (10) and / or the inner tube (18).

5. The apparatus for separating a gas from a fluid according to claim 2 or 3, characterized in that, The reversing space (26) is bounded by the inner tube (18), and the connection between the reversing space (26) and the interior (30) of the container (10) is located at the height of the relevant end portion.

6. The apparatus for separating a gas from a fluid according to claim 2 or 3, characterized in that The container (10), the connecting part and the guide device (16) are arranged concentrically with respect to their respective longitudinal axes, and when viewed in the axial direction, the guide device (16) extends from one connecting part (12) toward the other connecting part (14) and terminates at the center of the container (10) or below or above the center (70).

7. The apparatus for separating a gas from a fluid according to any one of claims 1 to 3, characterized in that, The container (10) is configured to be rotationally symmetrical with respect to its longitudinal axis (52).

8. The apparatus for separating a gas from a fluid according to claim 2 or 3, characterized in that, During operation of the device, fluid from the other connection point (14) on the inflow side is degassed by means of the guide device (16), and the gas is stored in the upper region of the container (10). As the fluid, having passed through the guide device (16) and having had its gas significantly removed, is discharged to the connecting portion (12) serving as the outflow side; and During the backwashing process in which volume flow reverses between the inflow and outflow sides, the gas that accumulates in the container (10) reaches the environment via the other connection point (14).

9. The apparatus for separating a gas from a fluid of claim 1, wherein, The device is used to separate air from hydraulic oil.

10. The apparatus for separating a gas from a fluid of claim 2, wherein, The at least two pipe fittings are arranged concentrically with each other.

11. The apparatus for separating a gas from a fluid of claim 7, wherein, The container (10) includes a container common to diaphragm accumulators, which consists of two housing halves (72, 74) that are pressure-sealed.

12. The apparatus for separating a gas from a fluid of claim 8, wherein, The other connection point can be connected to the storage tank (88, 98) of the hydraulic equipment.

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