GB2121318A

GB2121318A - Improvements relating to spray nozzles

Info

Publication number: GB2121318A
Application number: GB08215845A
Authority: GB
Inventors: Kenneth John Wilcox; Colin Beames
Original assignee: Smiths Group PLC
Current assignee: Smiths Group PLC
Priority date: 1982-06-01
Filing date: 1982-06-01
Publication date: 1983-12-21
Also published as: DE3317889A1; FR2527479A1; GB2121318B

Abstract

A spray nozzle, for projecting a washing liquid in droplet form on to a surface to be cleaned, for example on to the glasses or lenses of vehicle headlamps, comprises a nozzle body 1 having an elongated cylindrical internal chamber 5. The inlet aperture 6 of the nozzle is defined by the cross- sectional area of the chamber 5 at one end thereof. The outlet aperture 8 comprises a slot at the end of the chamber 5 opposite the inlet aperture, which slot extends peripherally of the chamber 5 at the junction between the side wall 9 and an end wall 7 thereof and for a distance less than half the periphery of the chamber 5. A partition wall 18 extends longitudinally of the chamber 5 from the inlet aperture to a position spaced from the end wall 7 to divide the chamber 5 into two sub-chambers 5a and 5b. The chamber 5b communicates with the outlet aperture 8 via the spacing between the end wall 7 and the partition wall 18. The body is adjustably mounted in the part- spherical recess of a washer head. <IMAGE>

Description

SPECIFICATION Improvements relating to spray nozzles This invention relates to spray nozzles for projecting a washing liquid in droplet form on to a surface to be cleaned, for example on to the glasses or lenses of vehicle headlamps, and which are capable of producing a cleaning action without the aid of a wiper element.

According to the invention a spray nozzle comprises a nozzle body having an elongated straight-sided internal chamber, the inlet aperture of the nozzle being defined by the cross-sectional area of said chamber at one end thereof, the outlet aperture comprising a slit at the end of said chamber opposite the inlet aperture, which slit extends peripherally of said chamber at the junction between the side wall and an end wall thereof and for a distance less than half the periphery of said chamber, and a partition wall extending longitudinally of said chamber from said inlet aperture to a position spaced from said end wall to divide the said chamber into two subchambers one of which communicates with the outlet aperture via the spacing between said end wall and the partition.

The invention will now be further described by way of example with reference to the accompanying drawings, in which:~ Figure 1 shows a sectional view of a nozzle according to the invention as fitted into the headlight washer of a vehicle, Figure 2 shows to a larger scale than Figure 1 a sectional view of the nozzle on the line Il-Il of Figure 3, Figure 3 is a view on the end of the nozzle containing the outlet aperture.

Referring to the drawings, the nozzle has a body 1 which fits into a washer head 2. The washer head 2 has a hose connector 3 by which it can be connected to a reservoir of washing liquid via tubing and a pump. The nozzle body 1 has a universal mounting in a spherical cup portion 4 of the head 2, so that the direction of the nozzle can be adjusted within desired limits.

The nozzle body 1 has an elongated cylindrical chamber 5. The inlet aperture 6 of the nozzle is defined by the cross-sectional area of the chamber 5 at one end thereof and lies within the spherical cup portion 4 of the washer head 2. Thus washing liquid supplied to the washer head 2 passes through the duct of the hose connector 3 and then through the cup portion 4 into the nozzle chamber 5.

The end of the chamber 5 opposite the inlet aperture 6 is defined by planar end wall 7 which extends at right angles to the longitudinal axis of the chamber 5. The outlet aperture 8 of the nozzle comprises an arcuate slot which extends peripherally of the chamber 5 at the junction between the end wall 7 and cylindrical side wall 9 of the chamber 5. The angular extent of the outlet aperture 8 as centred on the longitudinal axis of the chamber 5 is about 1200.

To provide the slot form outlet aperture 8, the generally domed head 10 of the nozzle body 1 has a cut-out sector in it to provide a flat surface 1 1 which extends at right angles to the longitudinal axis of the chamber 5 and which breaks into the chamber 5 at a distance from the end wall 7. The cut-out sector meets the remaining portion of the domed head 10 in a shoulder 12 which extends at right angles to the flat surface 1 The cut out sector may be formed by milling, or particularly in the case of nozzles made from plastics material may be formed by moulding.

The shoulder 12, as can be seen from Figure 3 has a generally curved 'W' shape to provide a central circular lobe 13 which is centred on the longitudinal axis of the chamber 5 and is set radially inwards of the cylindrical side wall 9. The lobe 13 is bounded on each side by circular cusps 14 and 15. The shoulder 12 extends from the cusps 14 and 15 in straight sections 16 and 17 up to the outer edge of the head 10. Thus the top edge (as seen in Figure 2) of the outlet aperture 8 is defined by the lobe 13 and the immediate adjacent portions of the cusps 14 and 1 5 on the shoulder 2 and the bottom edge of the outlet aperture 8 is provided by the flat surface 11 at its junction with the chamber side wall 9. The straight sections 16 and 1 7 of the shoulder 12 extend at an angle of about 1200 to each other.

A central partition 18 extends longitudinally from the inlet aperture 6 to a position spaced from the end wall 7 so that the upper edge (as seen in Figure 2) of the partition 18 is at a level just below the flat surface 1 The partition 18 extends completely across the chamber 5 on a diameter parallel to a straight line joining the ends of the slot-form outlet aperture 8 to divide the chamber 5 into sub-chambers 5a and Sb, the chamber Sb communicating with the outlet aperture 8 via the spacing between the end wall 7 and the partition 18. The partition 18 has side lugs at its lower end which locate in grooves in the chamber wall to locate the partition in position.

The partition 18 need not extend parallel to the aforesaid line and could extend on a chord rather than a diameter.

For the pressure of the order of 40-50 psi for the supply of washing liquid, e.g. water to headlight washers, the dimensions shown on Figures 2 and 3 may advantageously have the following values.

41 =9.75 mm 02 = 4-00 mm 43 =2.30 mm (through 1000 arc) a= 11.7 mum b=6.50mm c = 0.75 mm.

It has been found in trials that a nozzle of the above design with the provision of the two sub chambers, 5a and Sb through which streams of washing fluid are passed simultaneously from the inlet aperture 6 together with the other described features of the nozzle cause a droplet spray of generally square pattern to be projected from the nozzle having a desired velocity and spread to adequately clean the headlight glass of a motor vehicle without the aid of a wiper element.

In operation of the nozzle assuming it to be oriented as shown in the drawing the washing liquid is split into two flows in sub-chambers 5a and Sb respectively. The liquid passing through the slot 8 from sub-chamber 5a has an upward as well as a lateral component because as can be seen from Figure 3 the domed head 10 and hence the end wall 7 does not completely overlie the sub-chamber 5a. The whole of the liquid flow passing along sub-chamber Sb is deflected by the end wall 7 so that it is deflected into a lateral flow across the top of the chamber 5 and interacts with the upward flow of the liquid from the chamber 5a to influence the angle of the upward flow. The straight sides 16 and 17 of the shoulder 12 control the angular extent of the droplet spray laterally, i.e. in a plane perpendicular to the axis of the chamber 5.

Claims

1. A spray nozzle comprising a nozzle body having an elongated straight-sided internal chamber, the inlet aperture of the nozzle being defined by the cross-sectional area of said chamber at one end thereof and the outlet aperture being defined by a slot at the end of said chamber opposite the inlet aperture, which slot extends peripherally of said chamber at the junction between the side wall and an end wall thereof, characterised in that a partition wall extends longitudinally of said chamber from said inlet aperture to a position spaced from said end wall to divide the said chamber into two subchambers one of which communicates with the outlet aperture via the spacing between said end wall and the partition wall and the other of which communicates directly with the outlet aperture.

2. A spray nozzle according to Claim 1, wherein said chamber is cylindrical and said end wall is a planar end wall and extends at right angles to the longitudinal axis of said chamber.

3. A spray nozzle according to Claim 1 or 2, wherein said partition wall extends substantially parallel to a straight line joining the ends of said outlet aperture.

4. A spray nozzle according to any preceding claim, wherein one edge of said slot is provided by the chamber side wall and the opposite edge is provided by said end wall in such a manner that the end wall does not completely overlie said other of the sub-chambers.

5. A spray nozzle according to Claim 4, wherein said one edge of said slot is spaced from the end wall of said chamber and said partition wall extends to a position which is spaced further from said end wall than said one edge of the slot.

6. A spray nozzle according to Claim 4 or 5, wherein said opposite edge of the slot has a generally curved 'W' shape to provide a central circular lobe, which is centred on the longitudinal axis of the chamber, bounded by two circular cusps.

7. A spray nozzle substantially as hereinbefore described with reference to and as shown in the accompanying drawings.