WO1991019905A1

WO1991019905A1 - Improvements in or relating to pumps

Info

Publication number: WO1991019905A1
Application number: PCT/GB1991/000972
Authority: WO
Inventors: Richard Yonwin; Peter Edmund Reuben Mucci; Ronald William Woolley
Original assignee: Shumec Limited
Priority date: 1990-06-16
Filing date: 1991-06-17
Publication date: 1991-12-26
Also published as: GB9013490D0; AU8063991A

Abstract

A submersible pump (1) for displacing liquid fuel (2) (diesel oil) comprises liquid-displacing means in the form of a rotor (3) disposed in a casing (4). The casing (4) has a liquid fuel inlet (5) and a liquid fuel outlet (6). An electric motor (7) for actuating the rotor (3) is also provided, disposed within the casing (4). Rotation of the rotor (3) by the motor (7) results in liquid fuel (2) entering the casing (4) by way of the inlet (5) to be discharged therefrom by way of the outlet (6). The pump (1) further comprises a pump discharge pipe (8) connected to and extending away from the outlet (6), and electrical conductor leads (9a, 9b, 9c) connected to the electric motor (7), with a tubular casing (10) enclosing both the discharge pipe (8) and the leads (9a, 9b, 9c) in a liquid-sealing manner. The pump (1) is disposed in a container (15), which also houses the diesel fuel (2). The leads (9a, 9b, 9c) connect the pump motor (7), which is of brushless dc form, with a source (not shown) of electrical power, by way of a control board (16), mounted on top of the motor (7).

Description

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IMPROVEMENTS IN OR RELATING TO PUMPS

This invention relates to pumps and provides a pump which can be submersed in a body of liquid to be displaced by the pump.

The pump has particular application to the metered supply of liquid fuel to combustion-type air/water heaters used, for example, to heat the cabs of trucks and similar large road vehicles, as well as the cabins of boats.

According to the invention, a submersible pump for displacing liquid comprises liquid-displacing means disposed in a casing having a liquid inlet and a liquid outlet, electrical means for actuating the liquid-displacing means whereby liquid enters the casing by way of said inlet and is discharged therefrom by way of said outlet, a pump discharge pipe connected to and extending from said outlet, electrical conductor leads connected to the electric motor, and a tubular casing enclosing both the discharge pipe and the conductor leads in a liquid-sealing manner.

The liquid-displacing means preferably comprise a rotor.

The invention also comprises the combination of the pump and a container for holding liquid to be pumped.

The invention further comprises the combination of the pump, a container for holding liquid to be pumped and/or a combustion-type air heater.

The various aspects of the invention will now be described by way of example only, with reference to the accompanying drawings, wherein:

Figure 1 is a side view, partly in section, of the combination of a submersible pump according to the invention, and a container for holding liquid fuel to be pumped, Figure 2 is a fragmentary side view, in section, and to an enlarged scale, of part of the pump illustrated by Figure 1, and

Figure 3 is a semi-schematic side view, in section, of a combustion- type air heater.

With reference to Figure 1, a submersible pump 1 for displacing liquid fuel 2 (diesel oil) comprises liquid-displacing means in the form of a rotor 3 disposed in a casing 4. The casing 4, which is of cylindrical form, has a liquid fuel inlet 5 and a liquid fuel outlet 6.

Electrical means in the form of an electric motor 7 for actuating the rotor 3 are also provided, disposed within the casing 4. Rotation of the rotor 3 by the motor 7, which is coupled thereto, results in liquid fuel 2 entering the casing 4 by way of the inlet 5 to be discharged therefrom by way of the outlet 6.

The pump 1 further comprises a pump discharge pipe 8 connected to and extending away from the outlet 6, and electrical conductor leads 9a, 9b, 9c connected to the electric motor 7, with a tubular casing 10 enclosing both the discharge pipe 8 and the leads 9a, 9b, 9c in a liquid-sealing manner.

The pump 1 is disposed in a tank-like container 15, which also houses the diesel fuel 2. The leads 9a, 9b, 9c connect the pump motor 7, which is of brushless dc form, with a source of electrical power, by way of a control board 16, mounted on top of the motor 7.

The pump 1 is supported by a stand-off pipe 17 of resilient construction, which extends substantially vertically from the container bottom 15b, on which it rests. The bottom of the pump casing 4 is formed with a central spigot 4a which fits into the upper end of the pipe 17. The arrangement keeps the pump inlet 5, which comprises a ring of ports, clear of the container bottom 15b, so that any sludge 18 which may be present cannot enter the pump 1. As shown in Figure 2, the pump casing outlet 6 has an external screw thread 6a upon which a compression joint nut 20 is mounted. A compression sealing ring 19 is also provided. The lower end of the pump discharge pipe 8 is disposed within the pump casing 4.

When tightened, the nut 20 secures the lower end of the tubular casing 10 to the outlet 6 of the pump casing 4 in a liquid-sealing manner.

Where the tubular casing 10 leaves the container top 15a, the casing is secured thereto, in a sealing manner, by a compression joint 21 comprising a flanged connection 22 defining a bore which locates the casing 10, a rubber seal 23 of annular form disposed between the container top 15a and an extension-flange 22a of the connection 22, a nut 24 which is screwed onto the connection 22 so as to clamp the seal 23 in place, and a compression nut 25 which secures the casing 10 to the connection 22.

The pipe 8 and tubular casing 10 are preferably of plastics material.

At least the upper end of the tubular casing 10 is plugged with rubberised plastic or other sealant material, such as epoxy resin, so as to weatherproof the pipe 8 and leads 9a, 9b, 9c.

As shown in Figure 2, the upper end of the pump casing 4 contains potting compound material 28 which encapsulates adjacent portions of the pipe 8, as well as a sheath 29, within which the leads 9a, 9b, 9c are disposed.

With reference now to Figure 3, a combustion type air heater 30 is illustrated thereby.

The air heater 30 is mounted on a large road vehicle (not shown) and provides heated air to the cab 50 of the vehicle or other area which requires heating The air heater 30 comprises a casing 31 housing a combustion chamber 32, a heat exchanger 33, a fresh air fan 34, a combustion air fan 35, a fuel injector 36, a glow plug 37, an electric motor 38 for driving both fans 34 and 35, and a burner tube 39.

The air heater 30 further comprises a fresh air intake 45, a combustion air intake 46, a combustion exhaust 47 and a heated air outlet 48.

In operation, combustion air is drawn through the intake 46 by the fan 35 to mix with diesel fuel supplied by the injector 36. The glow plug 37 ignites the air/fuel mix in the combustion chamber 32. The hot gases resulting from combustion then enter the heat exchanger 33 by way of the burner tube 39 before escaping to atmosphere by way of the exhaust 47.

Fresh air to be heated is drawn into the heater 30 by way of the fan 34 and passes over the heat exchanger 33 to be raised in temperature thereby before discharge to the cab 50 of the road vehicle via the outlet 48.

The pump 1 of Figure 1 provides a metered supply of diesel fuel to the injector 36 by way of the discharge pipe 8.

The pump 1 is disposed within the tank-like container 15, in order to avoid pumping troubles sometimes caused by 'waxing' of diesel fuel in low temperature conditions. The pump 1 within the container 15 may be disposed substantially centrally.

The pump 1 and air heater 30 are preferably controlled by electrical/electronic control means disposed in the road vehicle so as to be operable by the driver thereof, or any other person.

The control board 16 need not be disposed in the proximity of the electric motor 7. One alternative position comprises in the proximity of the electrical/electronic control means referred to above.

Thhee pump rotor 3 may be replaced by any other suitable liquid fuel udiisplacing means. If necessary, the electric motor 7 may then have to be replaced by other actuating means more suitable.

Claims

1. The combination of a container for holding liquid fuel for a combustion-type heater, and a pump for discharging the liquid fuel to the heater, the pump being disposed within the container so as to be submerged by the liquid fuel when held by the container.

2. The combination of claim 1, wherein the container is for holding diesel fuel and the pump is disposed so as to be shielded from the effects of low temperature conditions outside the container, by fuel present in the container.

3. The combination of claim 1 or 2, and the combustion-type heater.

4. The combination of any one of claims 1, 2 or 3, wherein the pump comprises liquid-displacing means disposed in a casing having a liquid inlet and a liquid outlet, electrical means for actuating the liquid-displacing means whereby liquid enters the casing by way of said inlet and is discharged therefrom by way of said outlet, a pump discharge pipe connected to and extending from said outlet, electrical conductor leads connected to the electric motor, and a tubular casing enclosing both the discharge pipe and the conductor leads in a liquid-sealing manner.

5. The combination of claim 4, wherein the liquid-displacing means comprise a rotor.

6. The combination of claim 4 or 5, wherein the pump casing is disposed above the bottom of the container.

7. The combination of claim 6, wherein the pump casing is supported above the bottom of the container by resilient support structure.

8. The pump per se of claims 4, 5, 6 or 7.

9. The combination of claim 1, substantially as hereinbefore described, with reference to Figures 1 and 2 of the accompanying drawings.

10. The combination of claim 3, substantially as hereinbefore described, with reference to Figure 3 of the accompanying drawings.

11. A submersible pump, substantially as hereinbefore described, with reference to Figure 3 of the accompanying drawings.