WO1990003502A1

WO1990003502A1 - Replenisher for pressurised cooling system

Info

Publication number: WO1990003502A1
Application number: PCT/GB1989/001066
Authority: WO
Inventors: Alan William Dackombe
Original assignee: Alan William Dackombe
Priority date: 1988-09-24
Filing date: 1989-09-11
Publication date: 1990-04-05
Also published as: GB8822499D0; GB2224825A; GB8920318D0

Abstract

A replenisher for use with a pressurised cooling system for an internal combustion engine has a valve assembly including first and second parts which provide connection between the cooling system and an expansion tank, a third port, a valve arrangement adapted to maintain the third port closed, but openable to allow passage of coolant from the third to the first port and to close the second port, and a pump operable to pump coolant into the third port.

Description

REPLENISHER FOR PRESSURISED COOLING SYSTEM

This invention relates to a replenisher for a cooling system, particularly the cooling system of an internal combustion engine incorporated in a motor car or other vehicle. The invention also concerns a cooling system which includes such a replenisher.

Most cooling systems which are provided for internal combustion engines and the like are pressurised. The coolant is disposed in a closed circuit which includes passageways through the engine block and a heat exchanger such as a radiator, and the system operates at a pressure which is somewhat above atmospheric pressure, the system being normally refilled or replenished by way of a removeable cap, such as a radiator filler cap. Such systems are closed in order to avoid continual loss of coolant through evaporation.

Nevertheless, for most systems there is a steady though usually slight loss of coolant by way of minor leaks in the system or otherwise. Most coolant systems can tolerate a substantial loss of coolant but, as is well known, if the loss of coolant is too great, the engine temperature will rise significantly, and often quite quickly, causing seizure or other severe damage to the engine. Loss of coolant is usually highest during motoring at high speeds for long journeys. It is during these periods that the engine is labouring its hardest and the cooling system is at its most vulnerable. However, when a vehicle is in very heavy, slow-moving traffic, the cooling system loses the benefit of fast moving air through the grill of the radiator. At this point there is a danger of the coolant rising in temperature very quickly, resulting with boiling and egression of fluid from the cooling system via any weak point, however slight. If the driver is warned of the loss of coolant, as by means of the usual instruments for the purpose, it is prudent for the driver to stop and if possible replenish the coolant in the system. It is necessary however in these circumstances to allow the system to cool down before one can safely attempt to open an inlet such as a filler cap and replenish the coolant.

The present invention concerns a replenisher which can operate to replenish the coolant in such a coolant system without requiring cessation of a journey or requiring the engine to be stopped and allowed to cool.

According to one aspect of the invention, a replenisher for use with a pressurised cooling system for an internal combustion engine comprises a valve assembly including first and second ports for providing connection between the coolant system and an expansion tank for the system, a third port, a valve arrangement which is adapted to maintain the third port closed but on opening to allow passage of coolant from the third port to the first port and to close the second port, and a pump operable to pump coolant into the third port.

According to another aspect of the invention, a coolant system of an internal combustion engine and including an expansion tank further includes, between the said expansion tank and the remainder of the system, a valve assembly connected to a pump which can in operation pump coolant from a reservoir to the system by way of the valve assembly, the valve including means for maintaining normally closed a port to which the pump is connected and permitting the said port to open and providing closure of a port leading to the expansion tank. The valve assembly may include a flap valve member which is biassed, for example by means of an external spring, to keep the port leading to the pump normally closed. The pump may be operated either when desired by an operator or automatically in response to a monitor of the cooling system, and may be a small high pressure pump. Pumping of coolant from the reservoir through the port opens the valve against the bias. The arrangement is preferably such that the flap valve member or some valve member interlocked therewith closes the port that leads to the expansion chamber when the pump is replenishing the coolant in the cooling system. However, when the pump is inoperative the aforementioned flap valve will be closed and coolant may flow to and from the expansion chamber by way of the body of the valve.

BRIEF DESCRIPTION OF THE DRAWINGS

A cooling system employing a specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:-

Figure 1 shows a sectional view of ύne embodiment of the invention?

Figure 2 shows a sectional view taken on line II-II of Figure 1; and

Figure 3 is a schematic illustration of an internal combustion engine incorporating the embodiment of Figure 1.

DETAILED DESCRIPTION

Figures 1 to 3 illustrate, by way of example only, one embodiment of the invention. As shown in Figure 3, an internal combustion engine 1 is provided with a liquid coolant system 2 of known form, including hoses and appropriate passageways 3 through the engine block. As is usual, the coolant system includes an expansion tank 4 connected by way of a hose or other conduit 5 to the remainder of the system 2. It is well known that opening such a system before it is cooled down is hazardous.

Between the expansion tank and the system 2 is a valve assembly including a valve body 6 with ports 1 , 8 and 9. The first port 7 is connected to the coolant system 2 at some appropriate point. The second port 8 is connected to the expansion tank. The third port 9 is connected to a pump 10 which can in operation pump coolant from a reservoir 11 to the port 9. In this embodiment of the invention, illustrated in more detail in figures 1 and 2, the port 9 is closed by a flap valve 12 which may be biassed by means of a spring 13 to close the port 9. Under these circumstances there is free passageway for coolant between ports 7 and 8 and accordingly between the expansion tank and the system 2. When, owing to a desire to replenish the coolant in the system 2, the pump 10 is operated, the flap valve 12 opens against the bias to allow flow of coolant from port 9 to the port 7 and thence into the system 2. The valve member is so arranged that while this flow occurs the port 8 is closed in order to prevent coolant fluid from being pumped into the expansion tank. In this embodiment of the invention the port 9 is disposed at an oblique angle to the port 8 so that the flap valve 12 is forced to close the port 8 whenever the pump 10 is operating to provide coolant to the port 9.

Where a vehicle is not fitted with an expansion tank, it is envisaged that the same valve arrangement may be used connecting the first port (7) to the cooling system by way of the overflow pipe of a radiator cap. The second port (8) acts as a continuation of the overflow pipe and the third port (9) is connected to a pump (10). A replacement two way radiator cap (readily available) is fitted and the system then operates in exactly the same manner as above.

Claims

1. A replenisher for use with a pressurised cooling system for an internal combustion engine and comprising a valve assembly including first and second ports for providing connection between the cooling system and an expansion outlet for the system, a third port, a valve arrangement which is adapted to maintain the third port closed but on opening to allow passage of coolant from the third port to the first port and to close the second port, and a pump operable to pump coolant into the third port.

2. A cooling system of an internal combustion engine, including an expansion tank and further including, between the said expansion tank and the remainder of the system, a valve assembly connected to a pump which can in operation pump coolant from a reservoir to the system by way of the valve assembly, the valve including means for maintaining normally closed a port to which the pump is connected and permitting the said port to open and providing closure of a port leading to the expansion tank.

3. A system according to claim 2, in which the valve assembly includes a flap valve member which is biassed to keep the port leading to the pump normally closed.

4. A system according to claim 3 in which the arrangement is such that the flap valve member or a valve member interlocked therewith closes the port that leads to the expansion tank when the pump is replenishing the coolant in the cooling system and such that when the pump is inoperative the aforementioned flap valve is closed and coolant can flow to and from the expansion tank by way of the body of the valve.