Abstract:
The invention relates to a rotor nozzle, in particular for high pressure cleaning devices, having a nozzle housing which has a swirl chamber between an inflow opening for a fluid, in particular water, and a discharge opening, with a rotor inclined with respect to a longitudinal axis during operation being supported at its front end at a bearing, in particular at a cup-shaped bearing, in said swirl chamber and with the rotor being able to be driven to make a rotating movement around the longitudinal axis by fluid flowing into the swirl chamber, wherein an adjustment device is positioned in front of the swirl chamber for the speed regulation of the rotor and forces the inflowing fluid to make a rotary movement around the longitudinal axis for the generation of a rotating fluid field before the transition into the swirl chamber, and wherein the rotating fluid field is disrupted more or less pronouncedly on the transition into the swirl chamber in dependence on the position of the adjustment device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority of German Patent Application No. 10 2006 019 078.5 filed Apr. 25, 2006.  
       FIELD OF THE INVENTION  
       [0002]     The invention relates to a rotor nozzle, in particular for high pressure cleaning devices, having the features of the preamble of claim  1 .  
       SUMMARY OF THE INVENTION  
       [0003]     Rotor nozzles of this type are generally known.  
         [0004]     It is the object of the invention to further develop a rotor nozzle of the initially named kind such that the speed of the rotor can be regulated in a simple and reliable manner as precisely as possible.  
         [0005]     The object is satisfied by the features of claim  1 .  
         [0006]     The invention is based on the idea of generating a rotating fluid field before the transition to the swirl chamber and then to disrupt this rotating fluid field more or less pronouncedly on the transition into the swirl chamber. Depending on the position of the adjustment device, the rotating fluid field can thus propagate more or less unimpeded into the swirl chamber and can provide for the taking along of the rotor in the swirl chamber to drive it to make the rotating movement around the longitudinal axis.  
         [0007]     The invention thus, on the one hand, represents a turning away from those conventional rotor nozzles in which the rotating fluid field is only generated in the swirl chamber. On the other hand, the invention represents a turning away from known methods for speed regulation in which a so-called splitting of the inflowing fluid amount takes place in that some of the fluid is guided to the discharge opening while bypassing the swirl chamber with the help of bypass devices. It is, in contrast, not necessary due to the principle of the swirl field or rotating field disruption in accordance with the invention to guide some of the fluid past the swirl chamber by means of bypass devices. It is rather preferred in accordance with the invention for the fluid amount flowing into the swirl chamber per time unit to be constant, i.e. the invention does not work according to the principle of “amount splitting.” 
         [0008]     Furthermore, it is of advantage in accordance with the invention for no pressure difference to arise on the transition into the swirl chamber. Independently of how much the rotating fluid field is disrupted on the transition into the swirl chamber, the flow cross-sections at the transition can be dimensioned overall such that the fluid forming the rotating field does not have to overcome any resistance resulting in a pressure difference on the transition into the swirl chamber.  
         [0009]     Further preferred embodiments of the invention can be seen from the dependent claims, from the description and from the drawing. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The invention will be described in the following by way of example with reference to the drawing. There are shown:  
         [0011]      FIGS. 1   a  and  1   b  an embodiment of a rotor nozzle in accordance with the invention in two different operating positions;  
         [0012]      FIGS. 2   a  and  2   b  a further embodiment of a rotor nozzle in accordance with the invention in two different operating positions; and  
         [0013]      FIGS. 3   a  and  3   b  a further embodiment of a rotor nozzle in accordance with the invention in two different operating positions. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]     The rotor nozzles described in the following correspond to conventional rotor nozzles with respect to their general design so that a detailed description can be dispensed with in this respect.  
         [0015]     A cylindrical or pin-shaped rotor  21 , which is supported in a cup bearing  23  at its front end, is arranged in a nozzle housing  11  with a longitudinal axis  19 . A stopper  25  is screwed into the rear end of the nozzle housing  11 . The stopper  25  forms an adjustment device in accordance with the invention, which will be looked at in more detail in the following.  
         [0016]     The basic principle of such a rotor nozzle lies in the fact of driving the rotor  21  inclined with respect to the longitudinal axis  19  in the swirl chamber  17  to make a rotating movement around the longitudinal axis  19  in order to expel a conical fluid jet via the discharge opening  15  in this manner. For this purpose, a swirl flow or a rotating fluid field is generated in the swirl chamber  17  and provides a corresponding taking along of the rotor  21 . The fluid located in the swirl chamber  17  enters the rotor, for example, at the rear end of the rotor  21  and flows through the rotor  21  to the discharge opening  15  to there be expelled as a conical jet under high pressure.  
         [0017]     With conventional rotor nozzles, a drive bore opening radially or tangentially into the swirl chamber  17  is provided at the stopper  25 , for example, via which drive bore the fluid flows in the swirl chamber  17  such that the mentioned swirl flow arises into the swirl chamber  17 .  
         [0018]     In the embodiments of a rotor nozzle in accordance with the invention described here, the swirl flow or the rotating fluid field is not first generated in the swirl chamber  17 , but before the transition of the fluid from the stopper  25  into the swirl chamber  17 , and indeed at the stopper  25 . For this purpose, a ring passage  33  is provided which is bounded by a ring groove formed in the stopper  25  and the inner wall of the nozzle housing  11 , with the inner wall of the nozzle housing and the stopper  25  having a special cam section  39 ,  41  in this region which will be looked at in more detail in the following.  
         [0019]     The fluid enters into the ring passage  33  via an inflow space  35  formed in the stopper  25 . The fluid enters into the inflow space  35  via a supply line which is not shown and to which the rotor nozzle is connected during operation. The fluid supply line is in turn connected to a fluid source, in particular to a high pressure cleaning device.  
         [0020]     The inflow space  35  is in communication with the ring passage  33  via a drive bore  37  which opens, in particular radially or tangentially, into the ring passage  33  so that the fluid in the ring passage  33  is forced to make a rotating movement around the longitudinal axis  19 , whereby a rotating fluid field is generated. The rotating fluid field is therefore generated at the stopper  25  and not in the swirl chamber  17 .  
         [0021]     The screw-in depth of the stopper  25  into the rear end of the nozzle housing  11  can be set steplessly by screwing the stopper  25  in or out. A ring-shaped screw-in part  43  whose axial position is not varied relative to the nozzle housing  11  during operation serves as the rear abutment for the stopper  25 . A defined axial adjustment path is provided for the stopper  25  in this manner.  
         [0022]     In the embodiments described here, the fluid can always enter into the swirl chamber  17  from the ring passage  33  via one or more relief openings independently of the axial position of the stopper  25 . The embodiments described here each show two relief openings offset by 180° in the peripheral direction with respect to one another, and indeed an axially aligned relief bore  29  and a relief cut-out  31  which is, for example, produced by milling and is open radially outwardly, i.e. the cut-out  31  is an incision at the front marginal region of the stopper  25 .  
         [0023]     The relief cross-section, i.e. the sum of the flow cross-sections of all relief openings  29 ,  31  is selected such that it is larger than the cross-section of the drive bore  37  so that the drive bore  37 —seen in a technical flow aspect—so-to-say forms the “bottleneck” and there is also no pressure difference between the bring passage  33  and the swirl chamber  17  when—as in the positions in accordance with  FIGS. 1   a,    2   a  and  3   a —the relief openings  29 ,  31  form the only path for the fluid from the ring passage  33  into the swirl chamber  17 .  
         [0024]     The already mentioned cam profile  39  at the inner wall of the nozzle housing  11  in the region of the ring passage  33  of the stopper  25  cooperates with a cam profile  41  of the stopper  25 , with the cam profile  41  of the stopper  25  being formed by a front cam edge in these embodiments.  
         [0025]     In the closed position in accordance with  FIGS. 1   a,    2   a  and  3   a , the cam edge  41  contacts the inner wall of the nozzle housing  11  in a practically sealing manner. The stopper  25  and the nozzle housing  11  are worked to fit here. In this closed position, a transition of the fluid forming the rotating fluid field in the ring passage  33  into the swirl chamber  17  radially outwardly past the cam edge  41 , i.e. between the stopper  25  and the inner wall of the nozzle housing  11 , is not possible. Only the relief openings  29 ,  31  are available for the fluid. The fluid circulating in the ring passage  33  is consequently forced to make a change of direction, i.e. a flow deflection, which disrupts or destroys the rotating fluid field when flowing through the relief openings  29 ,  31 .  
         [0026]     The extent of the disruption of the rotating fluid field can—as experiments have shown—be influenced by the configuration and arrangement of the relief means  29 ,  31 . In the embodiments shown, the relief openings  29 ,  31  are oriented such that the fluid flows into the swirl chamber  17  substantially in the axial direction. Experiments have shown that even a slight inclination of the relief bore  29  relative to the longitudinal axis  19  has the consequence that the rotating fluid field is maintained to a relevant degree on the transition into the swirl chamber  17 . A rotary operation with a swirl flow taking along the rotor  21  in the swirl chamber  17  can therefore also be achieved in the closed position, i.e. in a position in which the fluid can only move into the swirl chamber  17  via the relief means or relief openings, on a corresponding configuration of the relief means.  
         [0027]     This means that an exceptional possibility is provided by the relief means to set the behavior of the rotor nozzle, and in particular the speed of the rotor  21 , directly.  
         [0028]     Just such a setting possibility is provided by the cooperation of the cam edge  41  of the stopper  25  and the cam profile  39  of the inner wall of the nozzle housing. As the comparison of  FIGS. 1   a  and  1   b  shows, a passage which is not interrupted in the peripheral direction and which has the form of a ring gap  27  arises between the cam edge  41  and the inner wall of the nozzle housing  11  on the unscrewing of the stopper  25  from the nozzle housing  11 , with the rotating fluid field being able to propagate or spread via said ring gap out of the ring passage  33  in an unimpeded manner in the axial direction into the swirl chamber  17  with respect to the peripheral direction. The size of the ring gap  27  and/or the rate of variation of the gap size on the adjustment of the stopper  25  relative to the nozzle housing  11  can be directly predetermined by the design of the cam profile  39  at the inner wall of the nozzle housing  11  and by a corresponding configuration of the cam edge  41  or of the corresponding region of the stopper  25 .  
         [0029]     In the embodiment of  FIGS. 1   a  and  1   b,  the cam profile  39  of the inner wall of the nozzle housing  11  is configured as a cone converging axially forwardly, whereas the stopper  29  is made as a corresponding cone in its axially front region.  
         [0030]     In the embodiment of  FIGS. 2   a  and  2   b , the inner wall of the nozzle housing  11  and the outer side of the stopper  25  are each made as cylindrically straight. The cam profile  39  of the nozzle housing  11  moreover includes a ring groove  45  which is formed in the cylinder wall and which is positioned in front of the cam edge  41  of the stopper  25  and coincides with the ring passage  33  with respect to the axial direction in the closed position in accordance with  FIG. 2   a . No ring gap is present between the cam edge  42  and the inner wall of the nozzle housing  11  in this closed position. This is different in the position in accordance with  FIG. 2   b . The cam edge  41  of the stopper  25  is located—with respect to the axial direction—in the region of the ring groove  45  of the nozzle housing  11  such that the fluid can flow out of the ring passage  33  radially outwardly around the cam edge  41  and can enter into the swirl chamber  17  while completely maintaining, or at least largely maintaining, the rotating fluid field.  
         [0031]     In the embodiment of  FIGS. 3   a  and  3   b , the inner wall of the nozzle housing  11  and the outer side of the stopper  25  are in turn made cylindrically straight, with the cam profile  39  of the nozzle housing  11 , however, being formed by a radially inwardly projecting ring shoulder  47  in the front region.  
         [0032]     The front cam edge  41  of the stopper  25  is made correspondingly rearwardly projecting so that the cam edge  41  contacts the ring shoulder  47  in the closed position in accordance with  FIG. 3   a , so that there is no ring gap at this point and so that the fluid forming the rotating fluid field in the ring passage  33  is thus forced to flow via the relief openings  29 ,  31  into the swirl chamber  17 .  
         [0033]     In the open position in accordance with  FIG. 3   b , in contrast, the cam edge  41  is radially spaced apart from the inner wall of the nozzle housing  11  so that a ring gap  27  is present around which fluid circulating in the ring passage  33  can flow while completely maintaining, or at least largely maintaining, the rotating fluid field in order to generate the swirl flow in the swirl chamber  17  providing the taking along of the rotor  21 .  
         [0034]     It was mentioned above that the cam edge  41  of the stopper  25  and the inner wall of the nozzle housing  11  can be worked to fit so that a practically complete seal of the ring passage  33  is provided in this region in the closed position. This cooperation region of the cam edge  41  and the inner wall of the nozzle housing can, however, generally be varied as desired. In the closed position, for example, a ring gap having a specific size could thus also be allowed, whereby a specific portion of the fluid can move into the swirl chamber  17  while maintaining the rotating fluid field. Furthermore, the control cam  41  or the inner wall of the nozzle housing  11  can also be made in knurled form. Further relief possibilities can hereby be provided.