Pressure gauge with mechanical locking function for hose couplings

Abstract

Pressure indicator device with mechanical detent function for hose couplings, characterized in that one or more blind bores (5) are arranged tangentially to the outer surface of the coupling housing (1) off-center, the axis of which is perpendicular to the axis of the coupling housing (1) and which are connected to the pressure-carrying interior (6), in each of which a pressure bolt (3) is slidably mounted, that a rotating ring (2) rotatable about the coupling axis is pushed onto the coupling housing (1) and covers the pressure bolts (3), that the end face of the pressure bolt (3) facing the pressure-carrying interior (6) is exposed to the internal pressure and the opposite end face acts mechanically on the inside of the rotating ring (2), and that the rotating ring (2) has on its inside sawtooth-like steps (7) with a flat flank (14) and a steep flank (15),wherein, when rotating in a first direction, the steep flank (15) forms an approximate positive fit against the pressure bolt (3), and when rotating in the opposite direction, the flat flank (14) generates a frictional fit against the pressure bolt (3) that increases progressively with increasing internal pressure.

Description

[0001] Technical field The invention relates to hose lines, in particular flexible hose connections with quick couplings for use in process engineering, hydraulics or pneumatics, which are operated under positive or negative pressure.

[0002] State-of-the-art hose assemblies serve as flexible connections in piping systems and differ from hoses by having fixed connectors at one or both ends, which enable a tight connection with other piping components.

[0003] They are used in process engineering for conveying fluids or in hydraulics for transmitting hydraulic / pneumatic energy. In these applications, they are frequently exposed to process conditions that include temperatures deviating from room temperature and, in particular, overpressures or underpressures.

[0004] Hose assemblies used in process engineering are frequently equipped with quick couplings, for example, lever arm couplings according to DIN EN 14420-7, tank truck couplings according to DIN EN 14420-6, or comparable systems according to DIN EN 14420 or similar standards. These enable quick, tool-free connection and disconnection of the hose.

[0005] Problems of the State of the Art: In operational practice, the current pressure state of a hose line is usually only indirectly or not at all discernible. Before disconnecting a hose line, the operator must ensure that there is no longer any overpressure. If this does not happen, the pressurized fluid will escape unhindered upon disconnection – especially with quick-release couplings.

[0006] US 2007 / 0246108 A1 solves this problem by mechanically preventing the two coupling halves from separating under pressure. However, this principle is designed for a specific coupling type and is not applicable to standardized quick-release couplings according to DIN EN 14420. Furthermore, contamination during harsh operating conditions can prevent the coupling from being reliably uncoupled, even when depressurized.

[0007] EP 0 343 325 A2 describes a pressure bolt on the handle of a pressure cooker, which is moved out of its housing as the internal pressure increases and drives an electric actuator to control the heat supply. Such a system is not feasible for quick couplings in hydraulics / pneumatics / process engineering.

[0008] Other pressure-indicating devices, such as pressure gauges or sensors, are generally not integrated into hose lines. For process-related reasons, such as explosion protection or to prevent damage, they are often mounted further away, making it difficult to determine the internal pressure of the coupling.

[0009] While leakage from fixed connections (flange, thread) can sometimes be partially limited by retightening the connection, this is no longer possible with quick-release couplings. After the release mechanism is activated, the coupling disconnects immediately and the fluid flows out freely.

[0010] Depending on the type and hazard potential of the fluid (toxic, flammable, hot, corrosive, etc.), such leaks can cause significant personal injury and property damage. For this reason, hose assemblies are largely treated the same as rigid pipelines in the Pressure Equipment Directive 2014 / 68 / EU and classified according to their hazard potential. Object of the invention

[0011] The invention is based on the objective of creating a pressure indicator device for hose couplings that displays the internal pressure mechanically and without an external energy source. The invention is achieved by features of the main claim. The dependent claims describe advantageous embodiments.

[0012] Further advantages and features of the invention will become apparent from the following description and the accompanying drawings. Technical solution / Nature of the invention

[0013] The invention consists in one or more blind holes (5) being arranged tangentially to the outer surface of the coupling housing (1) of the hose coupling, the axes of which are perpendicular to the axis of the coupling housing (1), in each of which a pressure bolt (3) is slidably mounted. The blind holes are drilled to a depth in the outer surface of the coupling housing (1) such that they are connected to the pressure-bearing interior (6). A rotating ring (2), rotatable about the coupling axis, is slid onto the coupling housing (1) and thereby covers the pressure bolts (3). The rotating ring (2) is axially secured against displacement by a spring ring (4).

[0014] The embodiment is designed with a socket with an internal thread connection (10) and an external thread connection (11). Alternatively, quick-release couplings according to DIN EN 14420 parts 6 to 8 can be used instead of the socket (10), and hose fittings according to DIN EN 14420 part 2 can be used instead of the external thread.

[0015] The end face of the pressure bolt (3) facing the pressure-bearing interior (6) of the clutch housing (1) is exposed to the internal pressure. The opposite end face of the pressure bolt acts mechanically on the inside of the rotating ring (2).

[0016] The rotating ring (2) has sawtooth-like steps (7) on its inner side, with a flat flank (14) and a steep flank (15). The flat flank (14) preferably has a small angle of inclination to the tangential plane, and the steep flank (15) has a large angle of inclination, preferably perpendicular to the tangential plane.

[0017] When rotating clockwise (13), the steep flank (15) comes into contact with the pressure bolt (3) and forms an approximate positive fit (9b). When rotating counterclockwise (12), the flat flank (14) comes into contact and, with increasing internal pressure, creates a progressively increasing frictional fit (9a).

[0018] This positive locking mechanism prevents the rotating ring (2) from turning clockwise even at low internal pressures. As the pressure increases, counterclockwise rotation also requires increasing manual force.

[0019] In the unpressurized state, the pressure bolt (3) is pushed back by the flat flank (14) when the rotating ring (2) is turned. Optionally, a pre-tensioned spring assists the return movement of the pressure bolt (3). The detent is released, and the rotating ring (2) can rotate freely in both directions.

[0020] In an alternative embodiment, instead of the sawtooth-like steps (7) on the inside of the rotating ring (2), individual dowel pins (8) are used, forming a contour elevation. The dowel pins (8) are arranged and oriented such that they form a steeper contact surface in one direction of rotation and a flatter contact surface in the opposite direction of rotation with the pressure bolt (3), thereby maintaining the asymmetrical locking effect (positive locking in one direction, progressive frictional locking in the other) (9c).

[0021] The free rotation in both directions serves as a reliable mechanical indicator that the interior (6) is depressurized and the hose coupling can be safely uncoupled. Fig. Figure 1 shows a pressure gauge in overall view. The coupling housing (1) with the rotating ring (2) slid onto it is visible. The interior (6) is pressurized when the pressure gauge is operated. The coupling housing is shown in the version with an internal threaded socket connection (10) on one side and an external threaded connection (11) on the other side. Fig. Figure 2 shows a cross-section through the pressure indicator device in the area of ​​the rotating ring (2). The cross-section reveals the blind bore (5) in the coupling housing (1), which is arranged tangentially to the outer surface of the coupling housing (1) and is connected to the pressure-carrying interior (6). The rotating ring (2) surrounds the coupling housing (1) coaxially and is axially secured against displacement by a spring ring (4). Fig. Figure 3 shows the pressure gauge device with a free-cut pressure bolt (3) in its installed position within the blind bore (5) of the coupling housing (1). The end face of the pressure bolt (3) facing the pressure-bearing interior (6) is exposed to the internal pressure. The opposite end face of the pressure bolt (3) is pressed against the inside of the rotating ring (2) under pressure. The pressure bolt (3) has indentations (9) on its outer surface, which prevent fluid from escaping from the pressure-bearing interior (6) along the pressure bolt (3). Fig. Figure 4 shows three detailed views of the resting function. Fig. Figure 3 (4a) shows the behavior when the rotating ring (2) is turned counterclockwise (12) under internal pressure. The flat flank (14) of the sawtooth-shaped step (7) comes into contact with the pressure bolt (3). With increasing internal pressure and thus increasing pressure bolt force, turning in this direction becomes progressively more difficult due to the increasing frictional engagement.

[0022] View (4b) shows the behavior when the rotating ring (2) is turned clockwise (13) under internal pressure: The steep flank (15) of the sawtooth-shaped step (7) engages the pressure bolt (3) and forms an approximate positive fit. Clockwise rotation (13) is therefore blocked even at low internal pressure.

[0023] View (4c) shows the corresponding behavior as in (4a) in the alternative embodiment with dowel pins (8). When rotating counterclockwise (12), the dowel pin (8) presses with its cylindrical surface against the end face of the pressure bolt (3) and pushes it back into the blind hole (5) against the internal pressure. The operating principle corresponds to the behavior described in view (4a).

[0024] View (4d) shows the corresponding principle as in (4b) in the alternative embodiment with dowel pins (8). When rotated clockwise (13), the dowel pin (8) abuts the cylindrical surface of the pressure bolt (3) and thus creates a positive fit. The operating principle corresponds to that of view (4b).

[0025] Fig. Figure 5 shows the rotating ring (2) in the version with sawtooth-shaped steps (7). The asymmetrical profile shape of the steps (7) with a flat flank (14) and a steep flank (15) is visible. The flat flank (14) has a small angle of inclination to the tangent plane, while the steep flank (15) is oriented almost perpendicular to the tangent plane.

[0026] Fig. Figure 6 shows the rotating ring (2) in the alternative embodiment with inserted dowel pins (8) forming a contour extension. The dowel pins (8), due to their cylindrical shape, generate the asymmetrical detent effect with respect to the pressure bolt (3). The dowel pins (8) project radially into the interior of the rotating ring (2), thus forming the contour extension that interacts with the pressure bolt (3). Reference symbol list: 1 clutch housing 2 rotating rings 3 pressure bolts 4 spring washers 5 blind hole drilling 6 Pressure-bearing interior of the clutch Stage 7: Contour enhancement of the rotating ring with steep and flat flanks 8 Contour enhancement as protruding locating pins 9 notches on the outer surface of the pressure bolt 10 Internal thread socket connection 11 External thread connection 12 counterclockwise rotations 13 clockwise rotations 14 flat flank on the rotating ring 15 steep flank on the rotating ring QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] US 2007 / 0246108 A1

[0006] EP 0 343 325 A2

[0007] Cited non-patent literature

[0000] DIN EN 14420-7

[0004] DIN EN 14420-6

[0004] DIN EN 14420 [0004, 0006, 0014]

Claims

[1] Pressure gauge device with mechanical locking function for hose couplings, characterized by, that one or more blind bores (5) are arranged tangentially to the outer surface of the coupling housing (1) off-center, the axis of which is perpendicular to the axis of the coupling housing (1) and which are connected to the pressure-bearing interior (6), in each of which a pressure bolt (3) is slidably mounted, that a rotating ring (2) rotatable about the coupling axis is pushed onto the coupling housing (1) and covers the pressure bolts (3), that the end face of the pressure bolt (3) facing the pressure-bearing interior (6) is exposed to the internal pressure and the opposite end face acts mechanically on the inside of the rotating ring (2), and that the rotating ring (2) has on its inside sawtooth-like steps (7) with a flat flank (14) and a steep flank (15),wherein, when rotating in a first direction, the steep flank (15) forms an approximate positive fit against the pressure bolt (3), and when rotating in the opposite direction, the flat flank (14) generates a frictional fit against the pressure bolt (3) that increases progressively with increasing internal pressure. [2] Pressure indicator device according to claim 1, characterized by , that the flat flank (14) has a small angle of inclination to the tangential plane and the steep flank (15) has a large angle of inclination, preferably approximately perpendicular to the tangential plane. [3] Pressure indicator device according to claim 1 or 2, characterized by , that the rotating ring (2) is axially secured against displacement by a spring ring (4). [4] Pressure display device according to any one of claims 1 to 3, characterized by , that each pressure bolt (3) is acted upon by a pre-tensioned return spring in the direction of the pressure-bearing interior (6). [5] Pressure display device according to any one of claims 1 to 4, characterized by , that in the unpressurized state the pressure bolt (3) is pushed back by the flat flank (14) when the rotary ring (2) is turned in the release direction, thereby releasing the detent and allowing the rotary ring (2) to rotate freely in both directions. [6] Pressure indicator device according to any one of claims 1 to 5, characterized by , that the free rotation of the rotating ring (2) in both directions of rotation serves as a mechanical indicator that the pressure-bearing interior (6) is depressurized. [7] Hose coupling, especially quick coupling, characterized by that it is equipped with a pressure indicator device according to one of claims 1 to 6. [8] Pressure indicator device according to any one of claims 1 to 7, characterized by, that the coupling housing (1) is designed as a socket with internal thread connection (10) and / or with external thread connection (11) and / or includes quick coupling principles according to DIN EN 14420 parts 6 to 8 and / or hose nozzles according to DIN EN 14420 part 2. [9] Pressure display device according to any one of claims 1 to 8, characterized by , that instead of the sawtooth-like steps (7) the contour increase is produced by inserted dowel pins (8) which form a steeper contact surface in one direction of rotation and a flatter contact surface to the pressure bolt (3) in the opposite direction of rotation.

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