Delivery nozzle with coated outlet pipe

Abstract

 A fuel delivery nozzle (1) has an outlet pipe (2) with a non wetting coating (26) to which fuel does not adhere and this prevents drips after the nozzle has been removed from a filler neck of a receptacle, and prevents contamination between subsequent transactions.

Description

[0001] The present invention concerns a delivery nozzle particularly for delivering fuel to a motor vehicle, the nozzle having an outlet pipe downstream of a fuel valve.

[0002] Such a delivery nozzle has been previously known from DE 19 71 586 8.4. The said delivery nozzle is capable of delivering different types of fuel, for which purpose the said delivery nozzle is connected to a multi-channel hose, so that different types of fuel are fed through different hose channels up to the fuel valve, downstream of the fuel valve the different fuel types pass through a common outlet pipe. After the termination of the fuelling process small residues of the fuel type last dispensed remain in the outlet pipe. After a fuelling process such residues could drip from the muzzle of the outlet pipe and could lead to contamination of the roadway or of the area around the filling station. In case of subsequent refuelling with a different type of fuel, residues could also contaminate the type of fuel drawn. This is of disadvantage especially in case of Diesel fuels.

[0003] According to the present invention there is provided a delivery nozzle incorporating a valve upstream of an outlet pipe, wherein at least the inner wall surface of the outlet pipe is coated with a material that can not be wetted, or that is manufactured from a material that can not be wetted.

[0004] When employing the present invention the inside of the outlet pipe is coated with a material which prevents wetting by fuel, or which is manufactured of such a material. As a result of such a design, residues form into droplets, which are repelled from the inner surface of the outlet pipe. Droplets are thereby prevented from adhering to the outlet pipe. Advantageously the coating extends around the muzzle of the outlet pipe onto its external surface. The coating material can be Teflon (PTFE) but other materials could be considered, such as PFA or a polyelectrolyte-tenside (PET) - complex. It is also suggested to use Sicon as a coating material. The coating may comprise several layers and it may be of advantage if the coating is electrically conducting.

[0005] The coating, or the material from which the outlet pipe is manufactured, should repel petrol and Diesel fuels. In a preferred arrangement the coating is applied to those delivery nozzles which are capable of delivering several different types of fuels that are taken to the said delivery nozzle by a multi-channel hose. For example, such a delivery nozzle is shown in the DE 19 71 586 8.4 and as far as the design of such a delivery hose is concerned, attention is drawn to that document. With this design a delivery nozzle, upstream of the valve, has several fuel channels connected. These fuel channels are preferably each closed by a non-return valve to prevent cross contamination of fuels. The invention is particularly advantageous when employed on a refuelling robot. By means of a programmed delay after fuelling, residues flow directly from the outlet pipe into the tank.

[0006] Where it is desired to employ a vapour recovery pipe arranged within the outlet pipe, or arranged alongside the outlet pipe, the wall surface of the said vapour recovery pipe is preferably also coated with a material that can not be wetted by fuel. Alternatively the vapour recovery pipe could also be made from a material which will not allow wetting by petrol and Diesel fuels.

[0007] One embodiment of the present invention is described below, by way of example only, with reference to the attached drawings of which:

Fig. 1 a delivery nozzle according to the invention,

Fig. 2 an enlarged cross sectional view through the outlet pipe of the nozzle of figure 1,

Fig. 3 a sectional view through the rear section of the delivery nozzle, containing the fuel valve,

Fig. 4 a sectional view through a multi-channel hose and

Fig. 5 a sectional view according to Fig. 2 with an integrated vapour recovery pipe.

[0008] Referring to figure 1a, delivery nozzle 1 comprises a knuckle bow 3, which contains an operating handle 4. Movement of the said handle 4 can open a fuel valve 25 contained in the delivery nozzle so that fuel exits from a multi-channel hose 5 (figure 3) through the outlet pipe 2.

[0009] The inside of outlet pipe 2 carries a coating 26, see figure 2, which extends from the muzzle 2' of outlet pipe 2 to the fuel valve 25 contained in the delivery nozzle. The said coating 26 also extends around the front face of muzzle 2' in a section 28 and continues along the outer surface of outlet pipe 2 in a section 27.

[0010] At the other end of the nozzle 1 an adapter 6 connects the nozzle to a multi-channel hose 5 to the delivery nozzle 1. The other end of the said multi-channel hose is connected to a delivery pump not shown. The adapter, depicted in Fig. 3 is described in detail in DE 19 71 586 8.4. The said adapter 6 comprises a fuel outlet section 23 which leads into the outlet pipe 2. The said fuel outlet section 23 is also coated and it terminates in the annular type fuel valve 25. Upstream of the fuel valve 25 the channel continues in sections 22 each of which leads to a non-return valve 20. Each of the fuel flow channels 16 of the multi-channel hose terminates in such a non-return valve 20 to prevent cross contamination of fuels.

[0011] In the example shown, a multi-channel hose 5 has a central vapour recovery channel 15 through which vapour, displaced by fuel entering the tank, can be captured. The said channel 15 continues in a vapour channel section 24 of delivery nozzle 1 to a vapour recovery pipe 29 which emerges in the region of the outlet pipe 2. The vapour recovery pipe 29 also has a coating 30, which may be applied to its inner and outer surfaces. The vapour recovery pipe 29 may also be placed alongside the outlet pipe 2.

[0012] Suitable coating materials are Teflon (PTFE) or PFA or a polyelectrolyte-tenside (PET) - complex. Another suitable material is Sicon. The coating may comprise several layers and it is also envisaged, that either the vapour recovery pipe 29 or the complete outlet pipe 2 may be manufactured from a suitable material, which can not be wetted by Diesel- or Petrol fuel.

[0013] Various modifications will occur to the skilled practitioner which will be within the scope of the invention, as defined by the appended claims. More particularly in the attached drawings a manual, or hand held nozzle, has been illustrated, however it is specifically envisaged that the invention is equally applicable to the nozzle of a robotic fuel dispenser.

Claims

1. A fuel delivery nozzle (1) incorporating a valve (25) upstream of an outlet pipe (2), characterised in that at least the inner wall surface of the outlet pipe (2) is coated with a material (26) that can not be wetted, or in that it is manufactured from a material that can not be wetted.

2. A nozzle (1) according to claim 1, characterised in that the coating (26, 27, 28) extends around the muzzle (2') of the outlet pipe (2) and along at least a portion of its outer surface.

3. A nozzle (1) according to one or more of the previous claims, characterised in that the coating (26, 28) consists of PTFE, PFA, a PET-complex or Sicon.

4. A nozzle (1) according to one or more of the previous claims, characterised in that the coating may consist of several layers

5. A nozzle (1) according to one or more of the previous claims, characterised in that the coating is electrically conducting.

6. A nozzle (1) according to one or more of the previous claims, characterised in that the coating repels both Petrol and Diesel fuels.

7. A nozzle (1) according to one or more of the previous claims, characterised in that the coating extends up to the fuel valve (25), incorporated in the delivery nozzle (1).

8. A nozzle (1) according to one or more of the previous claims, characterised in that upstream of the fuel valve (25) several fuel flow channels (16) enter the nozzle.

9. A nozzle (1) according to one or more of the previous claims, characterised in that the said several fuel flow channels (16) are each closed by a non-return valve (20).

10. A nozzle (1) according to one or more of the previous claims, characterised in that the delivery nozzle (1) is arranged to be mounted on a fuelling robot.

11. A nozzle (1) according to one or more of the previous claims, characterised by a vapour recovery pipe placed within, or alongside, the outlet pipe (2), the inner and/or outer surface of the vapour recovery pipe also being provided with a coating (30) which has fuel repelling properties.

Drawing