WO1995032804A1

WO1995032804A1 - Rotary nozzle for high pressure cleaning appliances

Info

Publication number: WO1995032804A1
Application number: PCT/EP1994/001755
Authority: WO
Inventors: Rolf Friedrich; Wolfgang Holzwarth
Original assignee: Alfred Kärcher GmbH & Co.
Priority date: 1994-05-30
Filing date: 1994-05-30
Publication date: 1995-12-07
Also published as: EP0762941B1; EP0762941A1; DK0762941T3; DE59406749D1

Abstract

A high pressure cleaning appliance has a housing (5) with a front wall (15) provided with a flat, centrally pierced depression (18). A nozzle body (21) with a passage (29) has a spherical end (20) supported in the flat depression (18), extends in the longitudinal direction over part of the housing (5) and has an outer diameter smaller than the inner diameter of the housing. An inlet (3) for a fluid tangentially opens into the housing (5) for causing the liquid to rotate in the housing (5) around the longitudinal axis, so that the nozzle body (21) rotates together with the rotating liquid and is supported on a circumferential supporting surface (25) against the inner wall of the housing (5), whereas the longitudinal axis of the nozzle body (21) is inclined with respect to the longitudinal axis of the housing (5). In order to increase the cleaning power of the rotary nozzle, the length (L) of the passage within the nozzle body (21) equals at least 70 mm, the ratio between the length (L) of the passage (29) and its diameter (d) equals 17 or more and a rectifier (30) is set into the upstream section of the passage (29). The rectifier (30) has parallel and diametrically opposed walls arranged in the passage (29), and the length (L) of the walls equals at least 0.25 of the length of the passage (29).

Description

ROTOR NOZZLE FOR A HIGH PRESSURE CLEANER

The invention relates to a rotor nozzle for a high-pressure cleaning device with a housing which is provided in a front wall with a pan-shaped, centrally perforated depression, with a nozzle body having a through-bore and which has a spherical end in the pan-shaped depression ab¬ supports, extends in the longitudinal direction over a part of the housing and has an outer diameter which is smaller than the inner diameter of the housing, and with an inlet opening into the housing in one direction for the liquid through which the liquid in the housing around the The longitudinal axis can be set in rotation so that the nozzle body rotates together with the rotating liquid and thereby lies against the inner wall of the housing with a bearing surface, the longitudinal axis of the nozzle body being inclined with respect to the longitudinal axis of the housing.

Such a rotor nozzle is known for example from DE 40 13 446 Cl. It has proven to be a very effective cleaning nozzle, since this nozzle can be used to generate a compact jet running around a cone jacket, with which a larger area can be achieved, the properties of the compact jet nevertheless being retained. This is also achieved with another known rotor nozzle, which, however, has a different drive principle, since in this known rotor nozzle the nozzle body is driven by a turbine or a paddle wheel (EP 0 379 654 B1). This is located in the area of a central, axially parallel liquid supply, so the liquid is not rotated in the interior of the housing as a whole, but the rotational movement of the nozzle body results from the impact of the incoming liquid on the blades of the turbine. The associated deflection of the liquid leads to a strong turbulence in the interior of the nozzle and thus to turbulent flow conditions. This in turn continues into the outlet area of the nozzle body, so that the cleaning action can be impaired by the turbulent flow.

It is an object of the invention to achieve an improvement in the cleaning effect in a rotor nozzle of the type described in the introduction.

This is achieved according to the invention in a rotor nozzle of the type described in the introduction in that the length of the through-bore in the nozzle body is at least 70 mm, in that the ratio of the length of the through-bore to its diameter has the value 17 or a greater value and that in the upstream section of the through hole, a rectifier with axially parallel and diametrically extending walls is arranged in the through hole, the length of which is at least 0.25 the length of the through hole. It has surprisingly been found that the specified features in combination lead to flow conditions in the nozzle body, by means of which the cleaning effect is increased.

This is probably due to the fact that the flow in the nozzle body can be very turbulence-free in this special embodiment, so that the jet emerging from the nozzle body remains very compact over a longer distance and does not fan out. This particularly turbulence-free flow results from the length, the large ratio of the length to the diameter and the large length of the rectifier used, but also from the combination of these dimensions with the drive principle described, in which the liquid in the The rectifier rotates as a whole and is not disturbed by turbine blades and their abrupt deflection. Since the nozzle body is carried along by the circulating liquid, the relative speed between the circulating liquid on the one hand and the circulating nozzle body on the other hand at the inlet of the nozzle body is low, so that in this area only minor flow disturbances when the liquid enters the nozzle body be occurring. These remaining slight flow disturbances can be eliminated by the special dimensioning of the through-hole and the rectifier to such an extent that a cleaning effect which was previously unattainable with known rotor nozzles can be achieved. It is advantageous if the diameter of the through hole is the same throughout, with the exception of the outlet area, that is, if there are no steps or constrictions in the through hole. Of course, the through hole in the outlet area will merge into the outlet opening of an outlet nozzle, and this outlet opening usually has a much smaller diameter than the through hole. It is also advantageous here if the transition from the through hole into the outlet opening of the nozzle takes place continuously, as is known per se.

According to a preferred embodiment of the invention it is further provided that the thickness of the walls of the rectifier is at most 1/40 of the total length of the rectifier. This is a very thin wall, which means that the flow through the through hole through the walls is minimally disturbed. This also promotes the uniformity of the flow through the through hole considerably.

It is advantageous if the rectifier is made of metal, since the higher strength values of metal compared to plastic mean that it is possible to work with smaller wall thicknesses without fear of damage to the rectifier and thus a change in the rectifier geometry .

In a preferred embodiment it can be provided that the width of the walls of the rectifier corresponds over most of its length to the inside diameter of the through hole, that the walls at the upstream end of the rectifier are slightly widened and that the widened parts of the walls merge into one Penetrate insert from deformable material that forms the inner wall at the upstream end of the through hole. It is thereby possible to fix the rectifier by axially inserting it into the through hole, since the widened ends of the rectifier dig into the deformable material and thus fix the rectifier in this position. At the same time, the walls bear most of their length against the inner wall of the through hole and thus divide the through hole into axially parallel and completely separate channels, which lead to the calming of the liquid.

It can be provided that a plastic ring which forms the deformable material is inserted into an enlarged section at the upstream end of the through-bore.

In a preferred embodiment of the rotor nozzle, it is provided that a nozzle insert with an outlet opening is arranged at the downstream end of the through bore, the outlet direction of which is inclined with respect to the longitudinal axis of the nozzle body.

Due to this inclination of the outlet opening in relation to the longitudinal axis of the nozzle body, the compact jet is no longer emitted from the nozzle body in the direction of the longitudinal axis of the nozzle body, but is inclined obliquely to this longitudinal direction, that is to say at an angle to this longitudinal direction. This longitudinal direction of the nozzle body at the same time forms the axis of rotation about which the nozzle body can rotate in the housing, so that this direction of the outlet opening also rotates on a cone shell, namely a cone shell, due to this intrinsic rotation of the nozzle body about its own longitudinal axis. whose axis coincides with the longitudinal axis of the nozzle body. After the nozzle body itself also rotates on a cone jacket, a complicated superimposition movement of the emitted compact jet is obtained in this way, namely, it first rotates according to the conical orbit of the nozzle body on a cone surface, and according to the intrinsic rotation of the nozzle body about its own longitudinal axis, this is superimposed Once again a conical orbit of the jet, this time in the extension of the longitudinal direction of the nozzle body itself. It is particularly advantageous in the case of the present embodiment that a very compact jet is formed by the upstream connection of the specially dimensioned through hole, which is deflected by the outlet opening with respect to the longitudinal axis of the nozzle body and at the same time retains its compact nature to the full extent . A very compact jet thus runs around a superimposed conical surface, and this means that when this compact jet strikes a surface, a circular strip is cleaned very effectively, since practically every point on the circular strip is struck by the very compact jet.

It is advantageous if the inclination of the outlet opening with respect to the longitudinal axis of the nozzle body is slight, for example in the range from 0.5 ° to 10 °, preferably from 1 ° to 5 ° and very preferably in the range between 2 ° and 3 , 5 °. A relatively slight inclination of the outlet opening relative to the axis of rotation of the nozzle body is therefore sufficient to achieve the desired effect.

In a first embodiment it can be provided that the nozzle body receives a nozzle insert in which an outlet opening is arranged which is inclined with respect to the longitudinal axis of the nozzle insert which is fitted axially parallel to the nozzle body.

In another embodiment, on the other hand, it is provided that the nozzle body receives a nozzle insert with an outlet opening arranged axially parallel in the nozzle insert and that the nozzle insert in the nozzle body is arranged with its own axis inclined with respect to its longitudinal axis. In these two solutions, the nozzle insert itself is therefore already manufactured with an outlet opening inclined with respect to the longitudinal axis of the nozzle insert, or a conventional nozzle insert with an axis-parallel outlet opening is inserted obliquely into the nozzle body.

The following description of a preferred embodiment of the invention serves in conjunction with the drawing to provide a more detailed explanation. Show it:

Figure 1 is a longitudinal sectional view of a rotor nozzle;

Figure 2 is a sectional view taken along line 2-2 in Figure 1;

3 shows an enlarged partial view of the outlet area of the rotor nozzle of FIG. 1 in a modified exemplary embodiment with a nozzle insert with an inclined outlet opening and

FIG. 4: a view similar to FIG. 3 in a further preferred exemplary embodiment with a nozzle insert with an axially parallel outlet opening which is inserted obliquely into the nozzle body.

The rotor nozzle shown in the drawing comprises a central screw connection 1, into which a high-pressure line (not shown in the drawing) can be screwed, through which cleaning fluid is supplied under high pressure. The screw connection 1 opens into a central blind bore 2 which is connected to the interior 4 of a housing 5 of the rotor nozzle via tangential bores 3 which run essentially transversely to the longitudinal direction of the blind bore 2. This housing 5 is formed by a hood-shaped housing cap 6, which is screwed onto an external thread 7 of a screw part 1 and the bottom part 8 receiving the blind hole 2. Housing cap 6 and base part 8 are sealed from the outside by an interposed ring seal 9. The base part 8 has a central projection 10 directed towards the interior 4, which between it and the inner wall of the interior 4 forms an annular space 11 coaxially surrounding the blind bore 2, into which the bores 3 open in such a way that the bores 3 liquid entering the annular space 11 is accelerated in the circumferential direction in the annular space 11. This results from the laterally offset arrangement of the bores 3, through which a component running tangentially to the circumferential direction is introduced into the flow.

The side wall 12 of the projection 10 which delimits the annular space 11 on the inside has an annular shoulder 13 on which the side wall 12 springs back in the radial direction in the direction of the interior 4. The interior 4 is cylindrical in the area adjoining the base part 8 and then merges into a conically narrowing section 14, which is finally closed by an end wall 15. In this end wall 15 there is a central opening 16 which widens in steps towards the interior 4. In this step-widened part 17 of the opening 16, a bearing body 18 is inserted, which can be made of ceramic, for example, and is sealed against the housing cap 6 by means of an annular seal 19. Towards the interior 4, this ring-shaped bearing body 18, which is arranged concentrically to the opening 16, is designed in the form of a spherically shaped pan, into which the spherical head 20 of a component which is referred to as the nozzle body 21 is inserted.

This nozzle body 21 essentially comprises a tube 22, with a constant outer and inner diameter, into which a nozzle insert 23 is inserted at the end on the bearing body side, which insert can also be made of ceramic, for example. This nozzle insert 23 is spherically shaped at its outer end protruding from the tube 22 and thus forms the head 20. In this nozzle insert 23 there is an outlet opening 24, the diameter of which is considerably smaller than the inside diameter of the tube 22.

On the outside, a rolling element 25 with a cross-section is attached to the tube, which can be made of polyurethane, for example, which is set relatively soft and which has a high friction with respect to the inner wall of the housing cap 6. This rolling element 25 is supported on an annular shoulder 26 on the outer wall of the tube 22 and is thereby fixed in one direction in the axial direction. The end of the tube 22 facing away from the bearing body 18 dips into the annular space 11 and keeps a small distance from the shoulder 13 which is so small that the nozzle body 21 in the housing can only be displaced in the axial direction by a very small distance and thus cannot exit with its head 20 from the bearing in the bearing body 18.

A plastic ring 28, which consists of a relatively soft, deformable plastic, is inserted into a step-shaped extension 27 at the rear end of the tube 22 opposite the bearing body 18.

At this end, a rectifier 30 is inserted into the through bore 29 of the tube 22 and, in the exemplary embodiment shown, has two walls 31 which are perpendicular to one another and run parallel to the through bore 29 and penetrate them diametrically. The width of these walls 31 is the same as the inside diameter of the through hole 29 over most of the length of the rectifier 30, so that axially parallel channels which are completely separate from one another are formed between each two walls 31.

At the rear end of the rectifier, the width of the walls 31 increases, so that the walls dig into the plastic ring 28 in this region of greater width when the rectifier 30 is inserted into the through bore 29 in the axial direction. This digging fixes the rectifier 30 in the through hole 29. The through hole 29 has the same inner diameter throughout, so that no steps or constrictions occur, except, of course, in the area of the nozzle opening 24. The length L of the through hole 29 is at least 70 mm, and the diameter d of the through hole 29 is chosen so small that the ratio Length L / diameter d assumes the value 17 or is greater. The length 1 of the rectifier 30 in the axial direction corresponds to at least 0.25 the length L of the through hole 29.

The rectifier 30 has particularly thin walls, namely the maximum thickness of the walls 31 is 1/40 of the length 1 of the rectifier. In order to achieve the necessary strength of the walls 31 in this case, the rectifier 30 is preferably made of metal.

In operation, the cleaning liquid supplied generates a rotational flow in the interior 4, in which the liquid inside the housing 5 rotates about the longitudinal axis of the housing. It takes along the nozzle body 21, which rests with the rolling body 25 on the inner wall of the housing 5 and rolls on it. As a result, the nozzle body 21 moves in the interior of the housing 5 on a cone shell, so that a compact cleaning jet emerging from the outlet opening 24 in the direction of the through bore 29 also rotates on a cone shell. This compact cleaning jet is particularly turbulence-free and compact due to the dimensions specified and is therefore particularly suitable for cleaning purposes. While in the exemplary embodiment in FIG. 1 the nozzle insert 23 has an outlet opening, the outlet direction of which lies exactly on the longitudinal axis of the nozzle body 21, so that the jet is emitted from the nozzle body exactly in the direction of the longitudinal axis of the nozzle body, the outlet direction is Outlet opening 24 in the embodiments according to FIGS. 3 and 4 is inclined with respect to the longitudinal axis of the nozzle body 21. This angle of inclination is on the order of 0.5 ° to 10 °, preferably a few degrees. As in the exemplary embodiment shown in FIG. 3, this can be done by using a nozzle insert 23 into which the outlet opening 24 is formed at an incline, or by a conventional nozzle insert 23 with an axially parallel outlet opening 24, the nozzle insert then being used 23 is inserted inclined in the nozzle body 21 (Figure 4).

In this way, an orientation of the jet emerging from the outlet opening is obtained, which depends in a complicated manner on the respective position and angular position of the nozzle body 21 in the housing 5. The nozzle body 21 is inclined relative to the longitudinal axis of the housing of the rotor nozzle by an angle which results from the fact that the nozzle body 21 rests with a rolling body 25 on the inner wall of the interior 4. The longitudinal axis of the nozzle body thus runs on a conical surface around the longitudinal axis. The axis of the outlet opening 24 and thus the direction of the emerging jet in turn run around the longitudinal axis of the nozzle body 21 on a cone jacket. The direction of the axis of the outlet opening 24 with respect to the longitudinal axis of the housing of the rotor nozzle thus results from a superimposition of the movements along these two conical surfaces. A particular advantage of the construction described is that the inclination of the outlet opening only takes place directly in the outlet area, so that overall a very long nozzle body 21 can be used, but this does not increase the width of the nozzle body.

This is extremely important, since otherwise a very bulky nozzle body would have to be used, which would have a large space requirement in the housing of the rotor nozzle, this would lead to a very large rotor nozzle. The fact that the inclination of the outlet opening is only generated in the outlet area by the nozzle insert means that a slender and nevertheless long nozzle body can be used, so that the housing of the rotor nozzle as a whole can also have a small outer diameter.

Claims

P A T E N T A N S P R Ü C H E

Rotor nozzle for a high-pressure cleaning device with a housing (5), which is provided in a front wall (15) with a pan-shaped, centrally perforated recess (18), with a nozzle body (21) having a through bore (29), which is with a spherical end (20) in the pan-shaped recess (18), extends in the longitudinal direction over part of the housing (5) and has an outer diameter which is smaller than the inner diameter of the housing (5), and with an inlet (3) opening into the housing (5) for a liquid, through which the liquid in the housing (5) can be set in rotation about the longitudinal axis, so that the nozzle body (21) together with the rotating liquid revolves around and lies with a contact surface (25) on its circumference against the inner wall of the housing (5), the longitudinal axis of the nozzle body (21) relative to the longitudinal axis of the housing (5) g is characterized, characterized in that the length (L) of the through hole in the nozzle body (21) is at least 70 mm, that the ratio of the length (L) of the through hole (21) to its diameter (d) is 17 or one has a larger value and that in the upstream section of the through hole (21) a rectifier (30) with axially parallel and diametrically extending in the through hole (29) arranged walls (31) is inserted, the length (1) at least 0.25 of the length (L) of the through hole (21).

2. Rotor nozzle according to claim 1, characterized in that the diameter (d) of the through hole (29) is the same throughout, with the exception of the outlet region.

3. Rotor nozzle according to claim 1 or 2, characterized gekenn¬ characterized in that the thickness of the walls (31) of the rectifier (30) is at most 1/40 of the length (1) of the rectifier (30).

4. Rotor nozzle according to one of the preceding claims, characterized in that the rectifier (30) consists of metal.

Rotor nozzle according to one of the preceding claims, characterized in that the width of the walls (31) of the rectifier (30) corresponds over most of its length (1) to the diameter (d) of the through bore (29) that the walls ( 31) are slightly widened at the upstream end of the rectifier (30) and that the enlarged parts of the walls (31) are inserted

(28) of deformable material penetrate the upstream end of the through hole

(29) forms the inner wall.

Rotor nozzle according to Claim 5, characterized in that a plastic ring (28) which forms the deformable material is inserted into an enlarged section (27) at the upstream end of the through bore (29).

7. Rotor nozzle according to one of the preceding claims, characterized in that at the downstream end of the through hole (29) is a Düsen¬ insert (23) with an outlet opening (24) is angeord¬ net, the outlet direction with respect to the longitudinal axis of the Nozzle body (21) is inclined.

8. Rotor nozzle according to claim 7, characterized in that the inclination of the outlet opening (24) relative to the longitudinal axis of the nozzle body (21) is 0.5 ° to 10 °.

9. Rotor nozzle according to claim 8, characterized in that the inclination of the outlet opening (24) relative to the longitudinal axis of the nozzle body (21) is 1 ° to 5 °.

10. Rotor nozzle according to claim 9, characterized in that the inclination of the outlet opening (24) relative to the longitudinal axis of the nozzle body (21) is 2 ° to 3.5 °.

11. Rotor nozzle according to one of claims 7 to 10, characterized in that the nozzle insert (23) is axially parallel to the longitudinal axis of the nozzle body (21) and has an inclined outlet opening (24).

12. Rotor nozzle according to one of claims 7 to 10, characterized in that the nozzle body (21) receives a nozzle insert (23) with an axially parallel in the nozzle insert (23) arranged outlet opening (24) and that the nozzle insert (23) in Nozzle body (12) is arranged with its own axis inclined relative to the longitudinal axis of the nozzle body (21).