EP1569755B1 - Nozzle assembly for a high-pressure cleaning device - Google Patents

Abstract

Nozzle arrangement for a high pressure cleaning device or a similar device comprises a nozzle hose (1) supporting a pot-shaped housing (3) which surrounds a seal connector (6) and in which a low pressure nozzle (12) and a high pressure nozzle (22) are mounted in a sealed manner against the inner wall of the housing so that they are freely displaceable. Displacement devices (31) move the low pressure nozzle and the high pressure nozzle in the housing in the longitudinal direction against and away from the seal connector. Preferred Features: The low pressure nozzle is prevented from rotating about the longitudinal axis of the housing. In the high pressure position the seal connector lies with an annular sealing section (7) made of an elastically deformable plastic material on a sealing surface (26) of the high pressure nozzle surrounding the seal connector. The sealing section is elastically widened on the action of the pressure of the conveyed liquid and is pressed in a sealing manner against the surrounding sealing surface.

Description

The invention relates to a nozzle assembly for a high-pressure cleaner or a similar device with a low-pressure nozzle, arranged in this high-pressure nozzle, with a jet pipe carrying a insertable into the high pressure nozzle seal, with a high pressure nozzle bypassing, leading to the low pressure nozzle bypass path and with displacement means, which change the distance between the sealing nozzle and the high pressure nozzle such that in a high pressure position of the sealing nozzle sealingly abuts the high pressure nozzle and thereby breaks the connection from the jet pipe to the bypass path, while in a low pressure position of the sealing nozzle is removed from the high pressure nozzle and thereby the connection from the jet pipe to Bypass path releases.

In high-pressure cleaners, there are various known constructions to selectively deliver via a jet pipe conveyed by the high-pressure cleaning device via a high-pressure nozzle, a low-pressure nozzle or a combination of two nozzles, so that the properties of the jet between the high pressure jet and low pressure jet can be adjusted substantially continuously. For example, it is known from EP 0 146 795, to keep the nozzles in a switching nozzle for high-pressure cleaning devices by the fluid pressure in the respective switching position. In this construction, the high-pressure nozzle insert is firmly connected to the jet pipe.

In EP 0 501 164 A1 a one-piece nozzle body is described in which a central high-pressure nozzle opening and low-pressure nozzle openings arranged parallel thereto are provided. The nozzle body can be moved relative to the feed pipe, this immersed in the advanced position in the high-pressure nozzle piece, the seal via O-ring seals on the plunging Zuflußstutzen.

From DE 196 13 391 A1, a further nozzle arrangement is known, in which a high-pressure and a low-pressure insert are displaced together, thereby releasing or closing bypass paths for the low-pressure jet. In this known jet nozzle, the high-pressure and the low-pressure inserts must be mounted on the jet pipe via a thread and twisted for displacement relative to this.

In all known constructions arise structurally complex and sometimes complicated structures, so that many parts are necessary, which must be processed in a special way to meet the complicated adjustment functions.

In EP-A-0 638 366 a generic nozzle arrangement for a high-pressure cleaning device is described, in which a sealing nozzle in an additional, leading to the high-pressure nozzle pipe piece can be inserted. This results in a relatively complicated and assembly-consuming construction.

Based on this prior art, the subject of the application, the task of forming a nozzle assembly of the generic type so that on the one hand a compact and on the other hand, a mounting-friendly nozzle assembly is obtained.

This object is achieved in a nozzle assembly of the type described above according to the invention that the jet pipe carries a pot-shaped housing which surrounds the sealing nozzle and in which the low-pressure nozzle and the high-pressure nozzle sealed against the inner wall of the housing are mounted freely displaceable, and that the displacement means the low-pressure nozzle and move the high-pressure nozzle in the housing in the longitudinal direction against the sealing nozzle and away from it.

In this solution, therefore, the jet pipe carries a cup-shaped housing, which serves as a bearing for the assembly of low-pressure nozzle and high pressure nozzle, this unit is simply inserted from the front into the housing and moved in this by the sliding movement more or less against the sealing nozzle. This is possible in a simple manner, and also the assembly of such an arrangement is very simple, since only the assembly of high and low pressure nozzle must be inserted into the cup-shaped housing, in addition, only the displacement means must be set on the jet pipe, which is the assembly of low-pressure nozzle and high pressure nozzle in the cup-shaped housing shifts.

It is advantageous if the low-pressure nozzle is secured by a rotation against rotation about the longitudinal axis of the housing.

A particularly preferred embodiment is obtained when the displacement means comprise a sleeve surrounding the pot-shaped housing, which is displaceable on the housing in the axial direction and thereby carries a low pressure nozzle more or less deeply into the housing einschiebende stop surface.

In particular, the sleeve can be rotatably mounted on the housing via a thread.

It is advantageous if the sleeve is composed of two half-shells, which can be applied from both sides to the housing.

A further advantageous embodiment results when the high pressure nozzle is inserted from the back into the interior of the low pressure nozzle and if stop means are provided which limit the insertion depth of the high pressure nozzle in the low pressure nozzle. The assembly of high pressure nozzle and low pressure nozzle is thus obtained simply by the fact that the high pressure nozzle is inserted from the back into the low pressure nozzle, in the retracted position it is held by the fluid pressure, special fixatives are not necessary.

The bypass path can be formed according to a preferred embodiment by longitudinal channels in the inner wall of the interior of the low-pressure nozzle, which are open to the interior and closed by the outer wall of the inserted high-pressure nozzle to the interior. This also leads to a structurally very simple solution, only the longitudinal channels, which can be formed by longitudinal ribs on the inside of the interior, are sufficient to form together with the inserted high-pressure nozzle in the longitudinal direction extending flow channels for the bypass path.

The longitudinal channels can be connected via lateral openings in the wall of the low-pressure nozzle with the interior of the cup-shaped housing.

Again, it is advantageous if the high pressure nozzle is secured by a rotation against rotation about the longitudinal axis of the housing.

In a very particularly preferred embodiment it is further provided that the sealing nozzle in the high pressure position at a sealing nozzle surrounding the sealing surface of the high pressure nozzle rests with an annular sealing portion which is elastically widened under the action of the pressure of the conveyed liquid and pressed sealingly against the surrounding sealing surface.

In this way, the inherent elasticity of the sealing portion is utilized to achieve sealing of the sealing nozzle against the interior of the high pressure nozzle when the high pressure nozzle is in the high pressure position. Additional sealant are not necessary, in particular O-ring seals can be omitted at this point. This also makes the structure of the overall arrangement very much easier.

The construction described can be realized particularly advantageous in the inventive design of a nozzle assembly, but this type of seal can also be used in other arrangements in which a seal between a jet pipe on the one hand and a nozzle body on the other hand must be made. In particular, this type of seal can also be used when a generic nozzle assembly of the type described above is used, in which the high-pressure nozzle and low-pressure nozzle are formed differently and the switching from high-pressure nozzle to low-pressure nozzle takes place in another way.

In such an arrangement with sealing between the sealing nozzle and high-pressure nozzle by elastic expansion of the annular sealing portion It is advantageous if at least the sealing portion consists of an elastically deformable plastic material. It is possible that the entire jet pipe is made in this way from the same plastic material.

In order then to achieve the required elasticity in the region of the sealing portion, it may be advantageous if the sealing portion has a reduced wall thickness in comparison to the wall thickness of the jet pipe.

In particular, the sealing portion is formed circular cylindrical.

The sealing surface of the high pressure nozzle is preferably formed circular cylindrical.

It is advantageous if in the flow direction of the sealing surface of the high pressure nozzle is followed by a narrowing in cross-section sealing region, this may be formed in particular conical. This narrowing in cross-section sealing area leads to a first seal between the sealing nozzle and the high-pressure nozzle when they are approaching each other. This first seal can increase the pressure of the pumped liquid in the interior of the high-pressure nozzle, since the bypass path is largely closed. This pressure increase then leads to a complete seal by elastic expansion of the sealing portion.

According to a preferred embodiment it is provided that the high pressure nozzle in the region of the sealing surface has a substantially lower elastic expandability than the sealing portion of the jet pipe.

For example, the high-pressure nozzle in the region of the sealing surface may have an increased wall thickness in relation to the remaining wall regions.

It is also possible that the high-pressure nozzle, at least in the region of the sealing surface, consists of a metal or a plastic of low extensibility, for example of brass or of a particularly tough polyamide.

Figur 1:

eine Seitenansicht eines Strahlrohres mit abgenommener Betätigungshülse;

Figur 2:

eine Längsschnittansicht durch eine Düsenanordnung im Hochdruckbetrieb;

Figur 3:

eine Ansicht ähnlich Figur 2 im Niederdruckbetrieb;

Figur 4:

eine perspektivische Ansicht einer teilweise aufgeschnittenen Baueinheit aus Niederdruckdüse und Hochdruckdüse und

Figur 5:

eine Schnittansicht längs Linie 5-5 in Figur 4.

The following description of preferred embodiments of the invention is used in conjunction with the drawings for further explanation. Show it:

FIG. 1:

a side view of a jet pipe with removed actuating sleeve;

FIG. 2:

a longitudinal sectional view through a nozzle assembly in high-pressure operation;

FIG. 3:

a view similar to Figure 2 in low pressure operation;

FIG. 4:

a perspective view of a partially cut assembly of low pressure nozzle and high pressure nozzle and

FIG. 5:

a sectional view taken along line 5-5 in Figure 4.

The nozzle assembly shown in the drawing comprises a jet pipe 1, which carries at one end a terminal 2 in the form of a bayonet, with the the jet pipe 1 can be connected to a supply line, not shown in the drawing, which in turn is fed by a likewise not shown, known per se high-pressure cleaning device. At the opposite end of the terminal 2, the jet pipe 1 is provided with a cup-shaped housing 3 arranged concentrically to the jet pipe, which has a closed bottom 4 toward the jet pipe and which is open on the opposite side. The interior of the housing 3 has a substantially circular cylindrical cross-section whose diameter is greater than the diameter of the jet pipe. 1

The interior 5 of the jet pipe 1 is connected to a sealing nozzle 6 in connection, which protrudes in the center of the bottom 4 of this and carries at its free end a thin-walled, circular cylindrical sealing portion 7. The adjoining the sealing portion 7 in the direction of the jet pipe 1 wall portion 8 has a substantially greater wall thickness than the sealing portion 7, this also applies to the jet pipe 1 in total. This is also made of a small extent elastically deformable plastic material, such as polyphthalamide (PPA), polyphenylene sulfide (PPS), polyacrylic ether ketones (PEEK), polyamide (PA) or polyethylene terephthalate (PET). These plastic materials can also be reinforced, in particular by glass fibers, while a glass fiber content of 10 to 50, in particular about 30%, is favorable.

On the outside, the pot-shaped housing 3 carries an external thread 9, which extends over the entire height of the housing 3, and at a small distance from the bottom 4 on the outside of the jet pipe 1 outwardly projecting stop elements 10 are formed.

In the circular cylindrical interior 11 of the cup-shaped housing 3 from the open front side of a low-pressure nozzle 12 is inserted, which has a substantially circular cylindrical outer wall 13 whose outer diameter substantially corresponds to the inner diameter of the cylindrical interior 11 of the housing 3. In this area, the outer wall 13 carries in a circumferential groove 14, a ring seal 15, so that the low-pressure nozzle 12 is sealed against the inner wall of the housing 3. The interior 16 of the low-pressure nozzle 12 is also circular-cylindrical, at the front, the jet pipe 1 facing away from the low-pressure nozzle 12, the interior 16 is closed like a dome and there has a larger outlet opening 17, while the interior 16 is open on the opposite side. In the inner wall extending in the longitudinal direction, open to the interior 16 through channels 18 are incorporated, which extend substantially the same over the entire length of the cylindrical interior to the dome-shaped end thereof. These channels 18 end at their end facing the jet pipe 1 in radially outwardly directed openings 19, in the region of these openings 19, the outer diameter of the low-pressure nozzle 12 is slightly smaller than the inner diameter of the inner space 11 of the housing 3, so that in this area the inserted low-pressure nozzle 12 is surrounded by an annular gap 20 which is bounded on the one hand by the annular seal 15 and on the other hand by the bottom 4 of the housing 3. This annular gap 20 is connected via the openings 19 with the channels 18 on the inside of the low-pressure nozzle 12 in connection.

At its end carrying the outlet opening 17, a radially projecting flange 21 is formed on the low-pressure nozzle 12, which is outside the cup-shaped Housing 3 is arranged and has a larger outer diameter than the interior 11 of this housing. 3

From the open rear side of the interior 16, a high-pressure nozzle 22 is inserted into this, which has a substantially circular cylindrical outer wall 23 whose outer diameter corresponds to the inner diameter of the inner space 16 of the low-pressure nozzle 12, so that when inserted high-pressure nozzle 22 this to the interior 16 of the low-pressure nozzle 12th towards open channels 18 closes (Figure 5). The high-pressure nozzle 22 is closed at one end hood-shaped and has at this end an outlet opening 24 whose outlet cross section is smaller than the outlet cross section of the outlet opening 17 of the low pressure nozzle 12, on the opposite side of the high pressure nozzle 22 is open and extends there via a conical sealing step 25 and goes upstream of this sealing step 25 in a circular cylindrical sealing surface 26 via.

The insertion depth of the high-pressure nozzle 22 into the interior 16 of the low-pressure nozzle 12 is limited by an annular flange 27, which rests at fully inserted high-pressure nozzle 22 at the rear end of the low-pressure nozzle 12. In this case, this annular flange 27 is flattened on opposite ends, the resulting flats 28 are covered by rear extensions 29 of the low-pressure nozzle 12, so that thereby the high-pressure nozzle 22 against rotation in the low-pressure nozzle 12 is received (Figure 4).

The pot-shaped housing 3, the low-pressure nozzle 12 arranged therein and the high-pressure nozzle 22 inserted into it are of two half-shells 30 surrounded, which together form a sleeve 31 when they are connected to the other components surrounding each other, for example by screws. On the inside, the half-shells carry 30 threads 32 in the form of juxtaposed, inwardly projecting projections 33, these projections 33 dive into the threads of the external thread 9, so that upon rotation of the sleeve 31, this is displaced in the longitudinal direction of the jet pipe.

On the inside, the two half shells 30 carry two inwardly projecting annular flanges 34 and 35, the front annular flange 34 rests against the outside of the flange 21, while the rear annular flange 35, the stop elements 10 of the jet pipe 1 engages behind. The dimensioning is chosen so that the sleeve 31 is adjustable only over a relatively small angular range and thereby performs a displacement of only a few millimeters, this shift is once limited by the fact that the annular flange 35 abuts the stop elements 10, on the other hand, that the low-pressure nozzle 12 can not be pushed further into the housing 3.

In a first position, hereinafter referred to as the low pressure position, the sleeve 31 is rotated so that it abuts with the annular flange 35 on the stop elements 10, the low pressure nozzle 12 and the high pressure nozzle 22 received therein can in this position of the sleeve 31 under the effect the conveyed through the jet pipe 1, highly pressurized liquid maximally pushed out of the housing 3, so that between the sealing nozzle 6 and the sealing surface 26 of the high-pressure nozzle 22 remains a gap through which the liquid emerging from the jet pipe 1 into the annular gap 20th can occur. The liquid thus stand two Flow paths available, namely, a first flow path through the high pressure nozzle 22 through to the outlet port 24, and a second flow path through the annular gap 20, the openings 19 and the channels 18 to the outlet port 17 of the low-pressure nozzle 12. Due to the relatively large outlet cross-section of the two outlet openings occurs Liquid with a relatively low pressure.

In the other end position, which is referred to below as the high-pressure position, the sleeve 31 is rotated so far that the low-pressure nozzle 12 and thus also the high-pressure nozzle 22 received therein are pushed into the housing 3 via the annular flange 34 to the maximum extent. During this insertion of the sealing nozzle 6 enters with its sealing portion 7 in the open end of the high pressure nozzle 22 and initially applies to the conical sealing step 25, so that the flow connection to the annular gap 20 is interrupted, but may not be complete without interposition of a seal. Nevertheless, this seal is sufficient to increase the pressure in the interior of the high pressure nozzle 22, and this pressure increase causes the circular cylindrical, thin-walled sealing portion 7 is pressed elastically outwards, he puts himself sealingly against the surrounding sealing surface 26 of the high-pressure nozzle 22 , And in this way, a complete seal that does not require the interposition of a sealing ring and also easily compensates for manufacturing tolerances. The liquid can thus escape only through the high pressure nozzle 22 and the outlet opening 24, the outlet cross section of the outlet opening 24 is relatively low, the outgoing jet is thus a high-pressure jet.

Between these two end positions, any intermediate positions are possible in which a more or less large part of the outflowing liquid is discharged through the annular gap 20 and the channels 18 through the outlet port 17.

The structure of the arrangement described is very simple, in particular, this results in great advantages during assembly. During assembly, it is sufficient to first push the high-pressure nozzle 22 into the interior 16 of the low-pressure nozzle 12, while neither a tool is necessary nor seals are needed. Subsequently, the low pressure nozzle 12 is inserted from the front into the housing 3, here the seal is ensured by only one ring seal. This arrangement is then surrounded by the two half-shells 30, which are applied from the outside to the housing 3 and connected to each other. Further assembly steps are not necessary, and also the number of used items is extremely low.

Claims (18)

1. Nozzle assembly for a high-pressure cleaning device or a similar device with a low-pressure nozzle (12), a high-pressure nozzle (22) arranged therein, a spray lance (1) bearing a sealing pipe connection (6) insertable into the high-pressure nozzle (22), a bypass bypassing the high-pressure nozzle (22) and leading to the low-pressure nozzle (12) and displacement elements (31) altering the distance between the sealing pipe connection (6) and the high-pressure nozzle (22) in such a manner that the sealing pipe connection (6) abuts sealingly on the high-pressure nozzle (22) in a high-pressure position and as a result interrupts the connection from the spray lance (1) to the bypass whereas in a low-pressure position the sealing pipe connection (6) is at a distance from the high-pressure nozzle (22) and as a result releases the connection from the spray lance (1) to the bypass, characterized in that the spray lance (1) bears a pot-shaped housing (3) surrounding the sealing pipe connection (6), the low-pressure nozzle (12) and the high-pressure nozzle (22) being mounted in said housing so as to be freely displaceable and sealed in relation to the inner wall of the housing (3), and that the displacement elements (31) displace the low-pressure nozzle (12) and the high-pressure nozzle (22) in the housing (3) in its longitudinal direction towards the sealing pipe connection (6) and away from it.
2. Nozzle assembly as defined in claim 1, characterized in that the low-pressure nozzle (12) is secured against any rotation about the longitudinal axis of the housing (3) by means of an element preventing rotation.
3. Nozzle assembly as defined in any one of the preceding claims, characterized in that the displacement elements comprise a sleeve (31) surrounding the pot-shaped housing (3), said sleeve being displaceable in an axial direction on the housing (3) and thereby bearing a stop surface (34) pushing the low-pressure nozzle (12) into the housing (3) to a greater or lesser depth.
4. Nozzle assembly as defined in claim 3, characterized in that the sleeve (31) is mounted on the housing (3) so as to be rotatable via a thread (9, 32).
5. Nozzle assembly as defined in any one of the preceding claims, characterized in that the high-pressure nozzle (22) is pushed into the interior (16) of the low-pressure nozzle (12) from the rear side and that stop elements (27) are provided, said elements limiting the depth of insertion of the high-pressure nozzle (22) into the low-pressure nozzle (12).
6. Nozzle assembly as defined in claim 5, characterized in that the bypass is formed by longitudinal channels (18) in the inner wall of the interior (16) of the low-pressure nozzle (12), said channels being open towards the interior (16) and being closed towards the interior (16) by the outer wall (23) of the inserted high-pressure nozzle (22).
7. Nozzle assembly as defined in claim 6, characterized in that the longitudinal channels (18) are in communication with the interior (11) of the pot-shaped housing (3) via lateral openings (19) in the wall of the low-pressure nozzle (12).
8. Nozzle assembly as defined in any one of claims 5 to 7, characterized in that the high-pressure nozzle (12) is secured against any rotation about the longitudinal axis of the housing (3) by means of an element preventing rotation (28, 29).
9. Nozzle assembly as defined in any one of the preceding claims, characterized in that in the high-pressure position the sealing pipe connection (6) abuts on a sealing surface (26) of the high-pressure nozzle (22) surrounding the sealing pipe connection (6) with an annular sealing section (7), said sealing section being expanded elastically due to the effect of the pressure of the liquid conveyed and being pressed sealingly against the surrounding sealing surface (26).
10. Nozzle assembly as defined in claim 9, characterized in that the sealing section (7) at least consists of an elastically deformable plastic material.
11. Nozzle assembly as defined in claim 9 or 10, characterized in that the sealing section (7) has a reduced wall thickness in comparison with the wall thickness of the spray lance (1).
12. Nozzle assembly as defined in any one of claims 9 to 11, characterized in that the sealing section (7) is of a circular cylindrical design.
13. Nozzle assembly as defined in any one of claims 9 to 12, characterized in that the sealing surface (26) of the high-pressure nozzle (22) is of a circular cylindrical design.
14. Nozzle assembly as defined in any one of claims 9 to 13, characterized in that a sealing area (25) narrowing in cross section adjoins the sealing surface (26) of the high-pressure nozzle (22) in the direction of flow.
15. Nozzle assembly as defined in claim 14, characterized in that the sealing area (25) narrowing in cross section is of a conical design.
16. Nozzle assembly as defined in any one of claims 9 to 15, characterized in that the high-pressure nozzle (22) has an elastic expandability in the area of the sealing surface (26) considerably less than that of the sealing section (7) of the spray lance (1).
17. Nozzle assembly as defined in claim 16, characterized in that in the area of the sealing surface (26) the high-pressure nozzle (22) has a wall thickness increased in relation to the remaining wall areas.
18. Nozzle assembly as defined in claim 16 or 17, characterized in that the high-pressure nozzle (22) consists of a metal or a plastic with low elasticity at least in the area of the sealing surface (26).

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