Device for cleaning the inner surface of a hose, pipe or channel

Abstract

Device for cleaning the inner surface of a hose, pipe or channel by means of a cleaning fluid, comprising a cleaning fluid line (1) and a nozzle head (2) arranged at its end, which has on its circumference an annular cleaning fluid outlet gap (13) that communicates fluidically with the cleaning fluid line (1) and serves to form an annular jet, wherein the annular cleaning fluid outlet gap (13) is bounded by two components (3; 5) that are rigid and dimensionally stable at the operating pressures for the cleaning fluid, the distance between which is adjustable in the area of ​​the cleaning fluid outlet gap (13) by screwing the two components (3; 5) together, and wherein the two components (3;5) having opposing, similarly oriented conical surfaces in the form of an inner surface (11) and an outer surface (10), which define an annular channel (12) whose opening forms the annularly circumferential cleaning fluid outlet slot (13), characterized in that the annular channel (12) tapers in the flow direction (D) such that twice the cone angle of the outer surface (10) is greater than twice the cone angle of the inner surface (11).

Description

[0001] The present invention relates to a device for cleaning the inner surface of a hose, pipe, or channel using a cleaning fluid, comprising a cleaning fluid line and a nozzle head arranged at its end, the nozzle head having an annularly circumferential cleaning fluid outlet gap that communicates fluidically with the cleaning fluid line and serves to form an annular jet. In particular, the present invention relates to a device, as defined in the preamble of claim 1, for cleaning the inner surface of a hose, pipe, or channel using a cleaning fluid.

[0002] During the manufacture of hoses, pipes, and similar components, contaminants can accumulate on the inner surface of the hose or pipe. These contaminants, for example, in the form of shavings, can occur when the hose or pipe is cut to length from a supply or when the end of a reinforced hose is peeled before a fitting is attached. Such contaminants must be regularly removed before further use of the hose or pipe, and typically even before the fitting(s) are attached, to prevent damage and / or malfunctions of other components (e.g., hydraulic units, etc.).

[0003] One established cleaning method involves using compressed air to propel a foam projectile, adapted to the inner diameter of the hose or pipe, through it. This projectile captures the dirt particles. However, this method is disadvantageous, particularly considering the amount of waste generated and the cost of the foam projectiles. Furthermore, in practice, a foam projectile frequently becomes stuck, requiring considerable effort for manual removal.

[0004] The aforementioned disadvantages are avoided if – according to another established method – the hose or pipe in question is flushed with air from one end to the other. However, due to the high flow rates required, this method typically demands a large volume of flushing air for the most reliable cleaning possible. Furthermore, there is a risk that this method will fail in the case of particularly stubborn or firmly embedded contaminants.

[0005] Other methods for internally cleaning a hose or pipe use a device comprising a cleaning fluid line and a nozzle head attached to its end. The device is inserted into the hose, pipe, or similar object with the nozzle head leading. Gaseous or liquid cleaning fluid is directed against the inner surface of the hose, pipe, or similar object by means of the nozzle head. For this purpose, several nozzle-like outlet openings may be provided, distributed around the circumference of the nozzle head. The at least one jet of cleaning fluid exiting the at least one outlet opening strikes the inner surface of the hose or similar object at high speed. For a good cleaning result, the jets exiting the nozzle head must cover the inner surface of the hose, etc., as thoroughly as possible. Known devices may provide this coverage.They feature a nozzle head that can rotate around its axis. Such devices with rotating nozzle heads are complex and delicate. The free rotation of the nozzle heads can easily become obstructed (e.g., by dirt) without the user noticing, leading to inadequate cleaning results. This phenomenon occurs particularly with more delicate devices designed for cleaning relatively thin hoses or pipes.

[0006] An alternative commonly encountered in practice is the device described in the introduction, in which the cleaning fluid exits the nozzle head in the form of an annular jet that reaches the entire inner surface of the hose or pipe. Relevant prior art in this regard is, for example, NO 318 420 B1. In the device known from this patent, the annular space used to form the radially outward-directed annular jet is bounded on one side by a rigid nozzle body and on the other by a resiliently compliant conical disc. At a defined cleaning fluid pressure, the resiliently compliant disc lifts away from the nozzle body at its circumference, thereby opening the annular exit gap and allowing the jet to exit the nozzle head.

[0007] From DE 39 06 579 A1, a device of the generic type is known which differs from the prior art according to NO 318 420 B1 in that the annularly circumferential cleaning fluid outlet gap is limited by two components that are rigid and dimensionally stable at the operating pressures for the cleaning fluid, the distance between which is adjustable in the area of ​​the cleaning fluid outlet gap by screwing the two components together, wherein the two components limiting the cleaning fluid outlet gap have opposing, conically oriented conical surfaces in the form of an inner surface and an outer surface, which limit an annular channel, the opening of which forms the annularly circumferential cleaning fluid outlet gap.In comparison to the device according to NO 318 420 B1, this method effectively ensures that a homogeneous annular jet is formed across the entire circumference of the nozzle head, as is necessary for consistently good cleaning performance. This is not the case with the device according to NO 318 420 B1; because, in practice, with increasing pressure in the cleaning fluid line, the resiliently compliant conical disc does not lift off the nozzle body uniformly across its entire circumference, resulting in a non-uniform annular jet around the circumference of the nozzle head. Particularly at comparatively low inlet pressures and / or low-viscosity cleaning fluids (e.g., air), the device known from NO 318 420 B1 even exhibits only localized lifting of the resiliently compliant conical disc from the nozzle body, thus preventing the formation of an annular jet altogether.This is fundamentally different in the device according to DE 39 06 579 A1.

[0008] DE 76 14 925 U discloses a compressed air cleaning gun for filter cartridges with a nozzle head arranged at the end of a blowpipe. This nozzle head comprises an annular nozzle, bounded by two ring nuts mounted on the blowpipe, with a radially oriented outlet slot, which is supplied with compressed air through openings provided in the blowpipe. The width of the outlet slot can be adjusted by adjusting the two ring nuts relative to each other.

[0009] Based on the prior art described above, the present invention aims to provide a device of the generic type that is further improved with regard to its suitability for practical use. Particular aspects of suitability for practical use are considered to be a high-quality cleaning result and high reliability of the device.

[0010] The problem stated above is solved by a generic device for cleaning the inner surface of a hose, pipe or channel, which is characterized in that the annular channel tapers in the direction of flow, such that twice the cone angle of the outer surface is greater than twice the cone angle of the inner surface.

[0011] The device according to the invention proves to be highly practical in the interaction of all its defining features. Due to the pressure-independent geometry of the outlet gap, an annular jet emerges from the outlet opening at a correspondingly low flow velocity, even at low inlet pressures and / or low fluid flow rates; this is even guaranteed with particularly low-viscosity cleaning fluids such as air or other gases. The identical orientation of the two conical surfaces bounding the annular channel, such that – unlike the prior art according to NO 318 420 B1 – one surface has the shape of an inner surface and the other the shape of an outer surface, ensures a very precise geometry of the annular jet – which widens conically from the cleaning fluid outlet gap – over a very wide range of flow conditions.This improves its reproducibility, enabling consistently good cleaning results across a wide range of applications. Because the annular channel tapers in the direction of flow, with the cone angle of the outer surface being twice that of the inner surface larger than twice that of the annular jet exiting the nozzle head, a particularly stable jet pattern is achieved. Especially for devices intended to operate (also) with air as the cleaning fluid, it proves very advantageous if the cone angle of the outer surface is 4° to 12°, preferably 6° to 10°, larger than twice that of the inner surface.

[0012] This, together with the adjustability of the nozzle head and its adaptability to different applications through the adjustable distance between the two components defining the annular cleaning fluid outlet gap by screwing them together, is crucial for the wide range of applications in which the device according to the invention can be operated, i.e., for the high application flexibility with consistently good cleaning results. The application flexibility even extends to the point that one and the same device can be easily adapted to cleaning fluids as different as air on the one hand and water on the other by simply screwing the components defining the annular cleaning fluid outlet gap together. The absence of moving parts during the intended operation of the device also contributes to its reliability.

[0013] According to a first particularly preferred embodiment of the aforementioned further development, the component with the conical inner surface has a larger outer diameter adjacent to the cleaning fluid outlet gap than the component with the conical outer surface. This supports high reproducibility with regard to the formation of the annular jet by allowing the formation of a defined separation edge for the annular jet at the aforementioned offset. Furthermore, this facilitates the formation of a directed outflow of the cleaning fluid in the annular space formed between the hose or pipe to be cleaned on the one hand and the nozzle head on the other.

[0014] Another particularly preferred embodiment of the aforementioned refinement is characterized by the presence of an annular distribution chamber upstream of the annular channel, which communicates with the annular channel and is supplied via at least one cleaning fluid channel. Such an annular distribution chamber can contribute to homogenizing the flow entering the annular channel, which in turn promotes the formation of a particularly homogeneous annular jet in the annularly circumferential cleaning fluid outlet gap. It is highly advantageous if a constricted annular zone is formed between the annular distribution chamber and the annular channel such that the flow cross-section upstream of the constricted annular zone, i.e., in the annular distribution chamber, and downstream of the constricted annular zone, i.e., in the inflow zone of the annular channel, is larger than in the constricted annular zone itself, which acts like a throttle.

[0015] In particular, an annular distribution chamber can be provided which is at least partially axially flowed through and which is preferably supplied with cleaning fluid from a pre-chamber, in particular a pre-chamber arranged centrally in the nozzle head, via at least one bore or at least one channel.

[0016] Several possibilities exist within the scope of the present invention for orienting a conically expanding ring jet. For certain applications, it can be advantageous for the ring jet to open conically away from the cleaning fluid line. This allows contaminants to be flushed forward out of the hose or pipe being cleaned, i.e., driven out of the hose or pipe in front of the device being successively inserted into the hose or pipe. This design is advantageous, for example, when contaminants of such dimensions are expected that they could become trapped in the annular gap between the hose or pipe on the one hand and the nozzle head and / or the cleaning fluid line on the other.If this is not the case, a reverse orientation of the conically expanding annular jet is typically advantageous, namely an orientation of the annular jet towards the rear in such a way that it opens conically towards the cleaning fluid line. The reduced cross-section of the annular gap between the hose or pipe on the one hand and the nozzle head and / or the cleaning fluid line on the other, compared to the free cross-section of the hose or pipe, results in a correspondingly high flow velocity of the outgoing cleaning fluid, which promotes the reliable removal of detached contaminants.

[0017] In the interest of a particularly pronounced flexibility with regard to the possible applications of the device according to the invention, according to another preferred embodiment of the invention, one of the two components which limit and define the annularly circumferential cleaning fluid outlet gap can be removed from the other component without damage and replaced with one that is geometrically differently designed.

[0018] According to yet another preferred embodiment of the present invention, the device for cleaning the inner surface of a hose, pipe, or channel with a cleaning fluid comprises a vibration generator which acts on at least one of the two components defining the annular cleaning fluid outlet gap such that their distance from each other in the region of the cleaning fluid outlet gap changes in an oscillating manner. Such an oscillation, which, through appropriate design of the vibration generator, can in particular be a high-frequency oscillation, imposes pressure pulsations on the annular jet flowing from the cleaning fluid outlet gap, which—by actively loosening firmly adhering contaminants—can contribute to a further improvement in the cleaning result.In this case, the (adjustable) mean distance around which the oscillation movement takes place can be considered the adjustable distance between the two components in the area of ​​the cleaning fluid outlet gap, which can be achieved by screwing the two components together.

[0019] The present invention will now be described with reference to a Fig. Figure 1 of the drawing illustrates a preferred embodiment, which is explained in more detail. The front end region of a device according to the invention is shown in an axial section.

[0020] The nozzle head 2 shown in the drawing, which is attached to the end of a cleaning fluid line 1, comprises two main components: a first component 3 in the form of a base body 4 and a second component 5 in the form of a jacket 6. The latter is screwed onto the bolt section 8, which has an external thread at the end of the base body 4, by means of an internal thread 7. This allows the axial relative position of the two components to be adjusted by rotating the jacket 6 and the base body 4 relative to each other. A lock nut 9 serves to fix the set position 7 of the jacket 6 and the base body 4 relative to each other.

[0021] Between the base body 4 and the jacket section 6, an annular channel 12 is formed, bounded by a conical outer surface 10 on the base body 4 and a conical inner surface 11 opposite it on the jacket section 6. Since the cone angle of the conical outer surface 10 (approximately 40°) is greater than twice the cone angle of the inner surface 11 (approximately 32°), the annular channel 12 tapers in cross-sectional area in the flow direction D, i.e., towards the annular cleaning fluid outlet gap 13 provided on the circumference of the nozzle head 2 and bounded by the base body 4 and the jacket section 6. As a result of the orientation of the annular channel 12 shown, the annular jet exiting the cleaning fluid outlet gap 13 opens conically towards the cleaning fluid line 1.The distance between the base body 4 and the jacket part 6 relative to each other in the area of ​​the cleaning fluid outlet gap 13, and thus the clear width of the latter, can be adjusted by screwing the base body 4 and the jacket part 6 relative to each other (as shown).

[0022] The annular channel 12 is supplied with cleaning fluid (e.g., water, possibly with additives, air, or the like) from the cleaning fluid line 1 via a centrally arranged pre-chamber 14, several cleaning fluid channels 15 in the form of radial bores 16 extending from the pre-chamber 14, and an annular distribution chamber 17. The latter is formed between and bounded by a substantially cylindrical outer surface section 18 of the base body 4 and an equally substantially cylindrical inner surface section 19 of the shell part 6; a ring flow R oriented parallel to the axis X is formed within it.

[0023] Between the annular distribution chamber 17 and the annular channel 12, a constricted annular zone 20 is formed such that the flow cross-section upstream of the constricted annular zone 20, i.e., in the annular distribution chamber 17, and immediately downstream of the constricted annular zone 20, i.e., at the inlet to the annular channel 12, is larger than in the constricted annular zone 20 itself, which acts like a throttle. The constriction is formed by an annular circumferential bead 21, which is formed on the shell part 6 and faces the cylindrical outer surface section 18 of the base body 4.

[0024] The fluid-carrying area of ​​the nozzle head 2 is sealed from the area serving as the mechanical connection between the base body 4 and the jacket part 6. For this purpose, a sealing ring 23 is received in an annular groove 22 provided on the base body 4, which bears against a cylindrical sealing surface 24 of the jacket part 6. In this way, a reliable seal is ensured even when the two parts are in different positions relative to each other (as shown).

[0025] Regarding the nozzle head shown: The two components defining the annular cleaning fluid outlet gap, namely the base body 4 and the jacket part 6, are rigid and dimensionally stable at the (design) operating pressures for the cleaning fluid and therefore do not deform. After loosening the lock nut, the jacket part 6 can be removed from the base body 4 without damage by unscrewing it and can be replaced with a jacket part of a geometrically different design. Adjacent to the cleaning fluid outlet gap 13, the component with the conical inner surface 11, i.e., the jacket part 6, has a larger outer diameter than the component with the conical outer surface 10, i.e., the base body 4.

Claims

[1] Device for cleaning the inner surface of a hose, pipe or channel by means of a cleaning fluid, comprising a cleaning fluid line (1) and a nozzle head (2) arranged at its end, which has an annular cleaning fluid outlet gap (13) on its circumference which communicates fluidically with the cleaning fluid line (1) and serves to form an annular jet, wherein the annular cleaning fluid outlet gap (13) is bounded by two components (3; 5) that are rigid and dimensionally stable at the operating pressures for the cleaning fluid, the distance between which is adjustable in the area of ​​the cleaning fluid outlet gap (13) by screwing the two components (3; 5) together, and wherein the two components (3;5) have opposing, similarly oriented conical surfaces in the form of an inner surface (11) and an outer surface (10), which define an annular channel (12) whose opening forms the annularly circumferential cleaning fluid outlet gap (13), ; characterized by , that the annular channel (12) tapers in the direction of flow (D) such that the twice cone angle of the outer surface (10) is greater than the twice cone angle of the inner surface (11). [2] Device according to claim 1, characterized by , that the double cone angle of the outer surface (10) is 4° to 12°, preferably 6° to 10° larger than the double cone angle of the inner surface (11). [3] Device according to one of claims 1 or 2, characterized by , that adjacent to the cleaning fluid outlet gap (13) the component (5) having the conical inner surface (11) has a larger outer diameter than the component (3) having the conical outer surface (10). [4] Device according to any one of claims 1 to 3, characterized by , that upstream of the ring channel (12) there is an annular distribution chamber (17) communicating with it and supplied via at least one cleaning fluid channel (15). [5] Device according to claim 4, characterized by , that an annular distribution chamber (17) is provided which is at least partially axially oriented and axially flowed through. [6] Device according to claim 4 or claim 5, characterized by , that between the annular distribution chamber (17) and the annular channel (12) a constricted annular zone (20) is formed such that the flow cross-section upstream of the constricted annular zone (20), i.e. in the annular distribution chamber (17), and downstream of the constricted annular zone (20), i.e. in the annular channel (12), is larger than in the constricted annular zone (20) itself. [7] Device according to any one of claims 1 to 6, characterized by, that the cleaning fluid outlet gap (13) is oriented such that the annular jet opens conically towards the cleaning fluid line (1). [8] Device according to any one of claims 1 to 7, characterized by , that one of the two components (3; 5) can be removed from the other component without damage and replaced with one that is geometrically differently designed. [9] Device according to any one of claims 1 to 8, characterized by , that it comprises a vibration generator which acts on at least one of the two components (3; 5) limiting the annularly circumferential cleaning fluid outlet gap (13) in such a way that their distance to each other in the area of ​​the cleaning fluid outlet gap (13) changes in an oscillating manner. [10] Device according to any one of claims 1 to 9, characterized by that it is operated with a gaseous cleaning fluid, in particular with air.

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