NOZZLE FOR JETTING A SELF-VIBRATORY FLUID STREAM

Abstract: A nozzle for jetting self-vibratory fluid stream, which comprises a main nozzle for forming a jet stream, side walls for producing eddies on the right and left rides of the jet stream while preventing the stream from sticking thereto, and claw-like portions contiguous to the side walls for dividing and dispersing the jet stream, so as to adapt the jet stream to curve to cause self-vibration by means of alternately generated eddies in the right of left space between the side wall and the jet stream and pressure difference caused by absorptive effect arising from wake, and to disperse the jet stream with the claw-like portions for spraying the fluid around widely, is very useful as a jet nozzle for the water spraying device and cleaning machine, Recognizing the importance of the claw-like portions at the outlet port of the self-vibratory fluid stream jetting nozzle as above, this invention provides a self-vibratory stream jetting nozzle usable for a long term, in which the claw-like portion is rounded or provided with a straight linear part rounded at the end thereof or the cross-section of the output port is curved inwardly so that flowing efficiency is raised with flowing loss reduced and variation in characteristics resulting from wear of the claw-like portion may be prevented.

Description: This invention relates to a nozzle for jetting a self-vibratory fluid stream, and more particularly to a nozzle for jetting without moving parts a self-vibratory fluid stream, provided with a rounded portion or a straight linear part rounded at an output port or provided with a output port with an inwardly curved cross-section so that flowing efficiency is raised. BACKGROUND ART Conventional water spraying devices (including a jetting nozzle), include a device such as a watering can with a system for directly jetting water through a plurality of pores and a device such as a sprinkler or the like for spraying water with a system mechanically moving a jetting nozzle. Moreover, a water spraying device disclosed in JP-A-49-1916 and JP-A-50-6644 etc., has a system comprising a main nozzle for forming a jet stream in a jetting nozzle, side walls for producing eddies on the right and left sides of the jet stream, and claw-like portions contiguous to the side walls for dividing and dispersing the jet stream, so as to induce the jet stream to curve to create self-vibration by means of the difference in the right and left eddies generated between the side walls and the jet stream, and to disperse the jet stream with the claw-like portions for spraying the fluid over a wide range. Of these conventional water spraying devices, the device such as a watering can with the system for directly jetting water through a plurality of pores,exhibits the disadvantage that the pores are inclined to become plugged with dust and the trajectory of the jet stream is short because of a large flowing resistance or the like. In addition, the device such as a sprinkler with the system mechanically moving a jetting nozzle, shows the disadvantage that mechanically moving parts are damaged and production costs are high because of the complicated structure or the like. Further, the water spraying device with a self-vibration system disclosed in JP-A-49-1916 and JP-A-50-6644 exhibits the disadvantage that an energy loss is largely produced by the impingement of the jet stream against the claw-like portions of the output port and the characteristics of the claw-like portion is changed by wear or the like. A nozzle for jetting a self-vibratory fluid stream according to the preamble of claims 1 and 2 is known from EP-A-0 197 346. This known fluidic oscillator is preferably used for issuing a defrosting jet of air upon a windshield of a vehicle. The nozzle has a pair of control ports adjacent to the downstream side of a nozzle and a continuous inertance loop interconnecting the control ports said continuous inertance loop being of a length and cross-section such as to maintain the frequency of oscillation in a preferred range. It is the object of the invention to provide a jetting nozzle which can stably produce a high-frequency self-vibration by a jet stream from a main nozzle, and in which flowing loss is small and variation in characteristics resulting from wear is small. SUMMARY OF THE INVENTION This object is solved according to the invention by the subject matter of claim 1 or claim 2. Preferred embodiments of the invention are subject matter of the subclaims. Thus, the self-vibratory stream jetting nozzle is an output port provided with a rounded claw-like portion so that exfoliation and contraction are restrained, flowing loss is reduced and adhesive action is increased to increase the angle of water spraying, as compared with the output port of the conventional self-vibratory stream jetting nozzle having an acute claw-like portion and a straight linear part contiguous thereto. Moreover, a stable vibration can continue over a long period because variations resulting from wear are prevented. Alternatively, the self-vibratory stream jetting nozzle is provided with an output port having a portion extending from a claw-like portion to a straight linear part curved inwardly in the cross-section thereof so that the flowing loss can also be similarly reduced to increase the volume of flow. Furthermore, the two systems above can be combined to provide an output port with rounded claw-like portions curved inwardly in cross-section so that the above effects are intensified. BRIEF DESCRIPTION OF DRAWINGS Fig. 1 is an exploded perspective view of an embodiment of the first alternative according to a self-vibratory fluid stream jetting nozzle of the present invention, Fig. 2 is a front view of the assembled nozzle, Fig. 3 is an exploded perspective view of another embodiment of the first alternative, Fig. 4 is a front view of the assembled nozzle, Fig. 5 (a), (b) are an assembled view and a sectional view taken along the line b-b' of the second alternative. BEST MODE FOR CARRYING OUT THE INVENTION In order to describe the present invention in more detail, the embodiments will be described hereunder with reference to the accompanying drawings. Fig. 1 is an exploded perspective view of an embodiment of the first alternative, Fig. 2 is a front view of the assembled self-vibratory fluid stream jetting nozzle. The device comprises, in combination: a plate C having a feeding port 1; a plate B comprising a main nozzle 2 for forming a jet stream connected to the feeding port 1, an air chamber defined by right and left walls 3, 3' and connected with the main nozzle 2, an output port 5 provided with right and left claw-like portions 4, 4' rounded on a radius R and leading to the walls 3, 3'; and a plate A with air ports 6, 6'. In addition, Fig. 3 is an exploded perspective view of another embodiment of the first alternative, Fig. 4 is a front view of the assembled nozzle, wherein right and left claw-like portions 4, 4' are rounded on a radius R and straight linear parts 7, 7' respectively lead to the claw-like portions 4, 4', and end parts leading to the straight linear parts 7, 7' are respectively rounded on a radius R. The self-vibratory action of these self-vibratory fluid stream jetting nozzles is similar to that of the devices disclosed in JP-A-49-1916 and the output port 5 is a little wider than the spreading width of the jet stream and fluid provided from the feeding port 1 becomes a jet stream through the main nozzle 2 and an eddy is generated between the jet stream and the wall 3 or 3' contacting the jet stream. Air between the jet stream and the wall on the opposite side is removed by the jet stream to produce a pressure difference between the right and left sides of the jet stream so that the jet stream is resultingly bent to the right or left. By repeating this action, a stable self-vibration is continued. In this case, the claw-like portions 4, 4' are not acute, but rounded on a radius R so that flowing efficiency is raised with flowing loss reduced. In addition, when the claw-like portions are acute, the characteristics as the spray angle, the distribution of the water spraying and the flowing characteristics or the like are largely changed resulting from wear, but when the claw-like portions are initially rounded, the claw-like portions do not appreciably change from wear, therefore these characteristics are not significantly changed. Fig. 5(a) is an assembled view of an embodiment of the second alternative, and Fig. 5(b) is a sectional view taken along line b-b in Fig. 5(a). In this alternative, the cross-sections of the portions from the claw-like portions 4, 4' to the straight linear parts 7, 7' at the outside thereof in the output port 5 are curved inwardly. In this case, the flowing efficiency is raised with flowing loss reduced and the characteristics are not changed from wear. Moreover, the first alternative and the second alternative may be combined to provide claw-like portions rounded and curved inwardly in cross-section so that the effects are even more outstanding. Next, the results of an experiment comparing the conventional self-vibratory fluid stream jetting nozzle disclosed in JP-A-49-1916 etc. and the self-vibratory fluid stream jetting nozzle of the present invention are shown. Results of experiment L L L ma C R ma R R I 0.35 0.62 0.62 0.66 0.39 0.39 0.66 0.64 0.68 0.45 II 0.43 0.77 0.79 0.82 0.46 0.44 0.83 0.92 0.84 0.48 III 0.60 0.66 0.76 0.76 0.65 0.60 0.71 0.82 0.78 0.67 Notes 1. the units in the table is 10 N/cm² 2. the supply pressure is 20 N/cm² 3. the figures give the averages of the upper 5 ranks INDUSTRIAL APPLICABILITY As described previously, the self-vibratory fluid stream jetting nozzle of the present invention achieves the following effects by providing the output port of the self-vibratory fluid stream jetting nozzle with the rounded claw-like portions and the output port curved inwardly in cross-section. (1) Flowing efficiency is raised with flowing loss reduced. (2) Variations in characteristics of the spray angle, the distribution of the water spraying and the characteristics of flowing or the like resulting from wear are prevented. (3) When the claw-like portions are rounded and the cross-section of the output port is curved inwardly, the effects are even more pronounced. Consequently, when these self-vibratory fluid stream jetting nozzles are applied to a water spraying device and a jetting cleaning machine, the washing ability or the like is even more increased.

Claims: A nozzle for jetting a self-vibratory fluid stream, comprising spaces defined at the right and the left of a main jet stream from a main nozzle (2) and of an output port (5) wider than the spreading width of the jet stream, so as to cause self-vibration without the provision of an inertance loop by means of alternately generated eddies in the right or left space and pressure difference caused by the absorptive effect arising from the wake, characterized in that the right and left walls (3,3) of the output port consist of an outwardly diverging rounded portion rounded on a radius and continuously leading to the walls (3,3') confining the right and left space so as to reduce flowing loss in the jet stream to raise flowing efficiency and to prevent variation in characteristics resulting from wear. A nozzle for jetting a self-vibratory fluid stream, comprising spaces defined at the right and the left of a main jet stream from a main nozzle, and an output port wider than a spreading width of the jet stream, so as to cause self-vibration without the provision of an inertance loop by means of alternately generated eddies in the right or left space and pressure difference caused by the absorptive effect arising from the wake, characterized in that the right and left walls (4,4') of the output port viewed in cross-section to the jet stream are curved inwardly so as to reduce flowing loss in the jet stream to raise flowing efficiency and to prevent variation in characteristics resulting from wear. A nozzle for jetting self-vibratory fluid stream according to claim 1, characterized in that the right and left walls (4,4') of the output port (5) viewed in cross-section to the jet stream are curved inwardly, so as to reduce flowing loss in the jet stream to raise flowing efficiency and to prevent variation in characteristics resulting from wear. A nozzle for jetting self-vibratory fluid stream according to at least one of claims 1-3, characterized in that said main nozzle (2) is formed in a plate (B), which is assembled with a plate (A) having air ports (6,6') and a plate (C), having a feeding port (1).

Inventors: NAKAYAMA YASUKI, OHKUBO MASAKANE, NAKAYAMA, YASUKI, OHKUBO, MASAKANE
Applicants: CREO UNI CO LTD, CREO-UNI CO., LTD.
Application year: 1990
Main classification: B05B1
IPC codes: B08B7, B05B1, B05B17, B08B3, F15C1