GB2216249A

GB2216249A - Controlling water flow through vehicle radiators

Info

Publication number: GB2216249A
Application number: GB8807593A
Authority: GB
Inventors: Victor James Watkins
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-03-30
Filing date: 1988-03-30
Publication date: 1989-10-04
Anticipated expiration: 2008-03-30
Also published as: GB2216249B; GB8807593D0

Abstract

A heat exchanger, for example an internal combustion engine radiator, comprises an inlet header subdivided into a plurality of sections, one of the sections providing unimpeded water flow through tubes 16, and each of the other sections including a temperature sensitive valve 36-48 which is adapted to open when the water reaches a predetermined temperature. Each of the valves operates at a different temperature to ensure a progressive increase of water flow through the radiator as the engine approaches its optimum operating temperature. <IMAGE>

Description

COOLING SYSTEM The present invention relates to a cooling system for engines and other apparatus from which there is a need to disperse heat during operation after reaching a specific working temperature. The present invention is particularly useful for internal combustion engines.

In general internal combustion engines generate heat during operation. On first start up, the engine is often cold and to be efficient it needs to reach an operating temperature such that the gaseous components required for operation are fed to the cylinders at an optimum temperature. In addition the lubrication oil is more efficient in lubricating the various moving parts of the engine at a temperature higher than the normal ambient temperature in which the engine is operated. Thus in general, combustion engines are supplied with cooling means. These may be water jackets around the engine from which water passses through a heat exchanger, generally called the radiator, which exchanges heat with cooler air passing through the heat exchanger.

In the case of a vehicle, the cooling air passes through by means of a combination of movement through the air together with a fan to speed the air flow. It is known that variable temperature fans can be used such that in the warm up period the fan does not operate and that the amount of air flowing through the heat exchanger is minimized.

The water coolant passing round the engine is generally pumped by means of a water pump which works in conjunction with the rotation of the engine such that the faster the engine moves the faster the coolant passes round the system. Thus on start up the water pump will move coolant at low temperature rapidly around the engine delaying the warm up period of the engine.

The present invention attempts to provide apparatus to improve the warm up period of the engine while still maintaining adequate coolant flow around the engine, particularly when the engine has reached its optimum operating temperature.

According to the present invention there is provided a heat exchanger for an engine producing heat in excess, the heat exchanger comprising coolant flow means, the coolant flow means being divided into more than one section, the first section being capable of having complete coolant flow therethrough the second and any further sections each being capable of having coolant flow therethrough, and each further including a temperature sensitive valve which is capable of opening when the coolant reaches a predetermined temperature.

The present invention also provides a unit for attachment to a conventional heat exchanger of a motor vehicle having a headportion and a body portion such that the heater exchanger head is replaced by the unit, the unit comprising a coolant inlet, at least two sections one of which allows open flow of coolant from the unit to the body of a heat exchanger, the other and any further sections each including a valve openable at a pre-determined temperature to allow coolant to pass from the coolant inlet to the body of the heat exchanger.

The unit may be used as a modification to an existing radiator or be part of a complete radiator.

Although a heat exchanger may be divided into 2 sections it is preferred that the heat exchanger is divided into multiple sections i.e. 3, 4, 5, 6, 7, 8 sections.

There is no limit to the number of sections that can be provided to regulate coolant flow although the preferred number is in the region of 2 to 10 sections preferably 5 or 6 sections.

It is preferred that the valve which is needed for each section of the heat exchanger is placed on the inlet side of the heat exchanger. The valve may be of any suitable type and can include electrical valves, bimetal strips, as well as conventional thermostatic valves as used in motor vehicles.

The present invention is presently used for internal combustion engines such as petrol engines, diesel engines and Wankel type rotary engines used for motor vehicles.

The heat exchanger of the present invention may have the heat exchangers arranged such that the valves open at different temperatures on warm up of the engine. It is alsopreferred that the opening temperature of each valve is different to allow a graduated temperature opening threshold across the heat exchanger.

The present invention will be further described by way of example only with reference to the accompanying drawings in which: Figure 1 shows diagrammatic side view of a heat exchanger of the present invention Figure 2 shows a plan view of the heat exchanger along the line A-A of Figure 1 Figure 3 shows an alternative arrangement for one section of a heat exchanger of the present invention Referring to Figure 1, the heat exchanger 10 has a coolant inlet 12 and a coolant outlet 14. The heat exchanger is divided into sections 16, 18, 20, 22, 24, 26 and 28. Each of the sections 16, 18, 20, 22, 24, 26, 28 has heat exchange tubes 30 passing from the inlet portion of the radiator 32 to the outlet portion of the radiator 34. This provides the conventional body of a normal radiator used in conjunction with an internal combustion engine.The inlet portion 32 of the radiator is further modified into sections each having a heat operable valve 36, 38, 40, 42, 44 and 46. The inlet portion of the radiator has a further fluid top up inlet 48 attached thereto. Alternatively the fluid top up inlet may be connected to a fluid header tank.

Each of the valves 36, 38, 40, 42, 44 and 46 isolate the coolant from the heat exchange tubes 30. The valves may be conventional radiator valves as shown in figure 4.

Increase in temperature causes expansion of the valve such that the valve is caused to open to allow fluid down through the cooling tubes. Each of the valves is adjustd to operate at a different temperature to ensure a progressive increase of coolant fluid through the radiator as the engine progressively nears its optimum operating temperature. The valves will open and close according to the temperature of the water passing through the heat exchanger to keep the temperature at an optimum level.

Referring to Figure 3 one section of the heat exchanger is shown having a valve system. In this case the value is operated by a coiled bimetal strip 50 attached to flap 52 having a pivoted axis 54 which pivots to cause the flat 52 to cover the heat exchange tubes 56.

When the coolant liquid contained within the heat exchanger is cold the bimetal strip causes the flap to block the coolant tube 56. As the coolant increases in temperature, the bimetal stip expands causing the flap to pivot allowing flow through the tubes 56.

On any number of alternative different thermostat arrangements can be used to section off different portions of the heat exchanger. Other thermostatic types include electrical thermostat, discus thermostats etc. A series of bimetal chips may be used directly over each of the heat exchangae tubes to open and close according to the temperature of the water passing into the heat exchanger.

Claims

CLAIM

1. A heat exchanger comprising of matrix, end chambers, valves, inlet manifold and outlet manifold. The valves fitted at matrix tube ends.

2. A heat exchanger as claimed in Claim 1 wherein the matrix ends are divided into sections.

3. A heat exchanger as claimed in Claim 1 and Claim 2 wherein a number of valves are fitted inside end chambers.

4. A heat exchanger as claimed in Claim 2 and Claim 3 wherein valve= are fitted and sections fitted.

5. A heat exchanger as in Claim 4 wherein valves are fitted or.to chamber or sections on the end or ends of the matrix with the matrix end chambers.

6. A heat exchanger as in any preceeding claim, wherein the bod-f i fitted with valves internally.

7. A heat exchanger as in Claim 6 provided with chambers and valves.

8. A heat exchanger substantially as described herein with reference to accompanying drawing.