GB1559534A

GB1559534A - Washing spray nozzles

Info

Publication number: GB1559534A
Application number: GB3684/77A
Authority: GB
Original assignee: Westfaelische Metall Industrie KG Hueck and Co
Current assignee: Westfaelische Metall Industrie KG Hueck and Co
Priority date: 1976-01-30
Filing date: 1977-01-28
Publication date: 1980-01-23
Also published as: GB1559533A

Description

PATENT SPECIFICATION

( 21) Application No 3684/77 ( 2 ( 31) Convention Application Nos.

2 603 517 2612 175 ( 33) ( 44) ( 51) ( 52) ( 11) 2) Filed 28 Jan 1977 ( 32) Filed 30 Jan 1976 23 March 1976 in Fed Rep of Germany (DE) Complete Specification published 23 Jan 1980

INT CL 3 B 05 B 1/04 Index at acceptance B 2 F 10 Al 3 10 A 3 C l O Dl X 2 W 8 A A 4 F 24 B 1 B 2 24 B 4 ( 54) IMPROVEMENTS IN OR RELATING TO WASHING SPRAY NOZZLES ( 71) We, WESTFXLISCHE METALL INDUSTRIE KG HUECK & CO of 4780 Lippstadt, Federal Republic of Germany a Company organised according to the laws of the Federal Republic of Germany, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed to be particularly described in and by the following statement:

The invention relates to a nozzle for causing a washing liquid to be applied in droplet form on to a washing zone, more particularly but not necessarily exclusively for use in the cleaning of transparent or translucent glasses in motor vehicles, such as lamp glasses, or even screens or windows.

According to the invention, there is provided a nozzle for the projection of a spray of washing liquid in droplet form onto an area to be washed and comprising a turbulence or swirl chamber having side walls defining a substantially constant cross-sectional area of the chamber over at least the major part of its length between opposite end faces of the chamber, an inlet aperture in one of said end faces for admitting liquid into the chamber, said aperture having a central longitudinal axis parallel to the side walls of said substantially constant cross-sectional area, an outlet aperture for the liquid in the chamber occupying a region between the end face opposite said one end face and the side walls adjacent said opposite end face such that it extends transversely into said cross-sectional area of the chamber, or being disposed at a stepped region of the side walls between a first side wall portion spaced axially and transversely from the inlet aperture and a second side wall portion spaced further axially from the inlet aperture than said first portion but closer transversely than said first portion, the projected area of the outlet aperture as seen in the direction of the axis of the inlet aperture extending into the projected area, as seen in the same direction, of the turbulence chamber cross 50 section situated directly before the outlet aperture in the direction of liquid flow.

The arrangement should be such that a portion of the liquid entering the turbu 55 lence chamber can pass directly out of the outlet aperture whereas the remainder is first of all deflected by the opposite end wall and thus ensures turbulent mixing in the chamber 60 When a wide surface has to be washed, and a nozzle is arranged close in front of it, the outlet aperture is required to be very wide With a circular cross-section for the turbulence chamber, this presents 65 the problem that the outlet aperture may be too large transverse to its width for the spreading of the liquid at least in the central region of the spray, so that the distribution of droplet density is insuf 70 ficiently uniform, and there is too high a droplet density in the central region of the zone being washed For this reason it is convenient according to a further feature of the invention that in the case of 75 wide spray patterns, with which the droplet density is still required to be substantially uniform over the entire surface, the upper and lower edges of the outlet aperture as viewed in the main outflow direc 80 tion for the washing liquid, are situated in a parallel relationship or are at least curved or inclined in the same direction as each other so as to avoid the central region of the aperture being too large 85 compared with the outer regions of the aperture.

If with certain surfaces which are to be cleaned the washing liquid droplet density is to be particularly high in the central 90 2 V.

U 2 2.

U -.

$ 2 " en W) '' 'Clh If) If) 1 559 534 1 559 534 region, conversely to what has just been said, it would be convenient for the upper and lower edges of the outlet aperture to be so shaped that one is convex to the other or both are bi-convex relative to one another, as seen in the main outflow direction.

To improve and intensify the turbulent effect in the chamber, advantageously the end face of the chamber situated opposite from tre inlet aperture is in the form of a concave surface, e g in a conical or spherical dome-shaped manner, since in this way the portion of the washing liquid flowing into the chamber which does not issue directly through the outlet aperture from the chamber is deflected more satisfactorily and effectively as regards producing the turbulent effect.

Some preferred constructional forms of nozzle according to the present invention will be described by way of example with reference to the accompanying drawings, wherein: Figs l to 4 are cross-sectional views of alternative nozzles with different constructions of turbulence chamber and Figs 5 to 7 show different constructional forms for the end face remote from the inlet aperture of the turbulence chamber of a nozzle according to the invention.

The washer nozzle which is shown in simplified schematic form in Fig 1 comprises a turbulence chamber l which is bounded by generated surface 2, although it is not essential to have a circular crosssection chamber, and opposed end faces 3 and 4 Situated in the end face 4, which is formed by an insert disc 5, is an inlet aperture 6 the longitudinal axis of which is here coincident with a central axis of the chamber Outlet aperture 7 is arranged in the region of transition between generated surface 2 and end face 3, in such a manner that the outlet aperture has a projected area both in the axial direction X and as seen from the direction Y which is at right angles thereto The washing liquid entering the chamber I partly passes directly out through the outlet aperture 7, but the remainder of the liquid impinges on the end face 3 and is deflected in the opposite direction It impinges again with the liquid entering the chamber, so that an intensive turbulent action is obtained The portion of washing liquid flowing directly through the chamber l is projected onto the regions of the washing zone which are furthest away The entire washing spray is projected obliquely from the nozzle and is composed of a thin curtain of water droplets extending over the entire width of the zone being cleaned and moving fanwise over the entire height of the 7 one The oscillation frequency in I this case, however, may be so high that it is scarcely detectable with the naked eye.

To improve the turbulent effect in the chamber and therefore in order to make the nozzle more efficient, the end face 3 7 is preferably given a concave shape, e g.

as the conical and dome-like shapes exemplified at 3 a, 3 b and 3 c in Figs 2 to 4 respectively, other parts of these alternative forms corresponding to features al-, ready described with reference to Fig I being indicated by the same reference numbers.

The constructions described are able to provide a washing spray in which the liquid E issues in droplet form and has such a droplet distribution that the droplet density in the regions of a washing zone adjacent the nozzle is just as great as the droplet density in regions of a washing E zone situated further away Also, the liquid is not atomised into the form of a mist but relatively large droplets are produced which burst when they strike against the surface which is to be cleaned 9 The mean direction of emission of the washing spray is oblique to the chamber axis and the greater the eccentricity of the inlet aperture to the opposite end wall of the chamber (the eccentricity being 9 towards the outlet aperture) the smaller the angle of obliquity at which the spray is emitted.

The size and shape of the washing zone sprayed with the washing liquid is defined 1 ( by the size and shape of the outlet aperture Furthermore the distribution of water as viewed over the surface being cleaned is also defined by the shape of the outlet aperture For a wider washing zone the 11 outlet aperture should also be made wider.

In the case of a turbulence chamber hayin a circular cross-section, if the outlet aperture were given an upper edge which followed the shape of a chord there would 11 again be a variation of the water distribution and therefore the droplet density as viewed over the entire surface to be cleaned In order to reduce this effect or to prevent it substantially the upper edge 11 8 of the outlet aperture 7 situated in the end face 3 preferably comprises a shape which is parallel to the lower edge 9 or at least curves or is inclined in the same direction The edge 8 can be given an 12 arcuate shave or can be in the form of an obtuse angle The object of this feature is to narrow the outlet aperture at its central region.

If the water distribution is reouired to 12 be non-uniform, that is to say if the droplet density is to be greater in the central rlane of the surface to be cleaned, the height of the outlet anerture 7 can be increased at its central region This is 13 -, A e i, { 1 559 534 effected by using an outlet aperture 7 whose upper and lower edges 8 and 9 are either one convex or are bi-convex relative to one another as viewed in the main outflow direction of the outlet aperture.

In principle all shapes of outlet aperture 7 are possible Constructional forms such as those shown in Fig 5 and Fig 6 have been found particularly suitable for the cleaning of motor vehicle headlight glasses, but of course these could be slightly modified without prejudicing the cleaning action to any marked extent More particularly the constructional form of turbulence chamber shown in Fig 2 has been found suitable for the aforesaid purpose.

A nozzle arranged in any of the forms illustrated has also the further advantage that it can be produced very easily by an injection moulding process, since the outlet aperture is situated so that it can be shaped by a ram moving in the main mould-closing direction A further advantage from the manufacturing point of view is that the inlet aperture can be situated on a central longitudinal axis of the turbulence chamber, since in this way it is not necessary to fix the position of the insert comprising the aperture precisely when the insert is symmetrically shaped.

Attention is drawn to our copending application (No 3 683/77) (Serial No.

1 559 533) filed simultaneously herewith that relates to washer apparatus in which the nozzles disclosed herein can be employed.

Claims

WHAT WE CLAIM IS:

1 A nozzle for the projection of a spray of washing liquid in droplet form onto an area to be washed and comprising a turbulence or swirl chamber having side walls defining a substantially constant cross-sectional area of the chamber over at least the major part of its length between opposite end faces of the chamber, an inlet aperture in one of said end faces for admitting liquid into the chamber said aperture having a central longitudinal axis parallel to the side walls of said substantially constant cross-sectional area, an outlet aperture for the liquid in the chamber occupying a region between the end face opposite said one end face and the sidewalls adjacent said opposite end face such that it extends transversely into said cross-sectional area of the chamber, or being disposed at a stepped region of the side walls between a first side wall Dortion spaced axially and transversely from the inlet aperture and a second side wall portion spaced further axially from the inlet 60 aperture than said first portion but closer transversely than said first portion, the projected area of the outlet aperture as seen in the direction of the axis of the inlet aperture extending into the projected 65 area, as seen in the same direction, of the turbulence chamber cross-section situated directly before the outlet aperture in the direction of liquid flow.

2 A nozzle according to claim 1 where 70 in said inlet aperture axes is the central axis of said chamber cross-sectional area.

3 A nozzle according to claim l or claim 2 arranged to produce a spray with a droplet density which is approximately 75 uniform over the spray pattern width, wherein respective end edges of the outlet aperture furthest from and nearest to the inlet aperture are situated in parallel relationship or are at least curved or inclined 80 in the same direction as each other as viewed in the main washing liquid outflow direction.

4 A nozzle according to claim 1 or claim 2 arranged to produce a spray with 85 an intensified droplet density in a central plane of the spray extending longitudinally of the mixing chamber, wherein the respective nd edges of the outlet aperture furthest from and nearest to the inlet aper 90 ture are so shaped that one is convex to the other or both are bi-convex relative to one another, as viewed in the main outflow direction.

A nozzle according to any one of 95 the preceding claims wherein said opposite end face is in the form of a concave surface.

6 A nozzle according to claim 5 wherein said opposite end face is domed 100

7 A nozzle for the projection of a spray of liquid in droplet form onto an area to be washed, constructed and arranged for use and operation substantially as described herein with reference to any 105 one of the embodiments illustrated in the accompanying drawings.

8 A vehicle glass washing apparatus, comprising at least one nozzle according to any one of the preceding claims 110 MEWBURN ELLIS & CO Chartered Patent Agents 70-72 Chancery Lane, London WC 2 A IAD Agents for the Applicants Printed for Her Majesty's Stationery Office by The Tweeddale Press Ltd, Berwick-upon-Tweed, 1980.

Published at the Patent Office, 25 Southampton Buildings, London, WC 2 A l AY, from which copies may be obtained.

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