WO1992014129A1

WO1992014129A1 - Radiator flow tester

Info

Publication number: WO1992014129A1
Application number: PCT/AU1992/000033
Authority: WO
Inventors: Nigel Valentine Borissow
Original assignee: OSAT Pty Ltd
Current assignee: OSAT Pty Ltd
Priority date: 1991-01-31
Filing date: 1992-01-31
Publication date: 1992-08-20
Anticipated expiration: 1993-07-31

Abstract

A method and apparatus for testing for blockage of a radiator of a vehicle. An air passageway (1) is connected to the radiator, and air is caused to low through the air passageway and the core of the radiator. The rate of air flow or air pressure through the air passage gives a sensitive measure of the degree of blockage of the radiator and is measured from a gauge (8). An air bleed valve (9) can be provided to allow for calibration of the apparatus against a reference (30), and a reference card (31) can be provided for each vehicle as an easy means for assessing the extent of blockage of the radiator.

Description

RADIATOR FLOW TESTER

BACKGROUND OF THE INVENTION

This invention relates to an apparatus and method for testing blockage in the radiator of a vehicle.

The term radiator used in this specification refers to the heat exchanger through which coolant for an internal combustion engine passes so as to exchange heat with passing air. Such radiators include a core comprising a plurality of tubes communicating between two reservoirs, and typically having metal fins radiating from the tubes to enhance the heat exchange capabilities of the radiator.

In the state of the art there exists no easily used means for testing the extent to which the core of a radiator is blocked. As a consequence of finding that an engine is overheating, the extent to which a radiator is blocked is very rarely tested. Often a mis-diagnosis leads to the extra expense for the motorist of having a radiator disassembled and cleaned or simply replaced when that is simply not necessary.

It is an object of the present invention to provide a method and apparatus for testing the extent of blockage of a radiator which is both simple to use and effective.

SUMMARY OF THE INVENTION

It has been discovered that by placing the radiator core in line with an air passage way, the variation in pressure or air flow within the air passage way gives a very sensitive measure of the extent to which the radiator is blocked.

Thus one form of the invention could be said to reside in a method of testing for blockage of a radiator including the step of placing the radiator core in communication with an air passage way, the step of effecting an flow of air through the air passage way and thie step of measuring the pressure or air flow within the air passage way. In an alternative form the invention could be said to reside in an apparatus for testing the extent of blockage of a radiator, including connector means to connect the core of a radiator to an air passage way, an air pump means for creating an inner flow or air pressure within the air passage way, and gauge means to measure and display the air flow or pressure within the air passage way.

The air pressure within the air passage way is preferably negative and therefore the air pump means can suck air through the radiator core. This form of the invention is preferable because the tendency with positive pressure is to expand tubing elements of the apparatus and of unreliable readings because of the consequent risk of leaks occurring in the air passage way.

An alternative however is to provide a positive pressure air pump means can be provided to blow air through the radiator core.

The means to measure the air flow or pressure can be placed in communication with the same side of the radiator as the air pump means or at an opposite side.

A difficulty encountered is that the restriction in air flow caused by radiator cores varies greatly from one type of radiator to another. The means available for measuring air pressure or air flow is usually adapted only to measure or display within a relatively restrictive range. It is found that air flow or air pressure is varied radically by minor changes in the dimensions of flow path and the variation in restriction in flow caused by the different types of radiator cores used in vehicles is such that means for measuring the respective parameters over the entire range needed are not readily available.

Thus the invention in a further preferred embodiment includes means to adjust the air flow or air pressure within the air passage way so that the air flow or air pressure can be adjusted to fall within the range measurable by the means to measure the air flow or air pressure. Preferably this takes the form of a bleed valve.

_* A further difficulty arises from the fact that the air pump means may not be constant over an extended period of time in the air flow or air pressure that it provides and therefore the air flow or air pressure within the air passage way may need to be adjusted to a reference before testing a given type of radiator.

In a preferred form of the invention the adjustment of airflow or air pressure before measurement is best done with the connecting means communicating with a restriction aperture and the adjustment means being adjusted until the display is adjusted to a reference point, said restriction means having a restriction smaller or greater than the restriction caused by an unblocked radiator core of the type intended for testing. In that way the gauge means gives a reading greater than zero blockage compared to the reference point.

The above embodiment become quite important where radiators of small core dimensions are used, the calibration of the air flow or air pressure is best done with a restriction means corresponding approximately to the restriction of the unblocked radiator.

A reference indicator can be provided for each given type of radiator to indicate in conjunction with the gauge means the extent to which the radiator is blocked. Because of the large range of radiators available the operator may not refer to appropriate table correctly and the use of the reference indicator enables the user to be sure that he has made a correct diagnosis.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding the invention will now be described with reference o a preferred embodiment.

FIG. 1 is a diagrammatic representation of the layout of an embodiment of the invention, showing a radiator connected by a flexible hose to an air passage way and showing the relationship of the means to adjust air flow and the means to measure air pressure,

FIG.2 is a perspective view from the rear of a preferred embodiment of the invention with a back panel removed showing details of the layout of the air passageway, together with the air pump and air bleed valve, and the air pressure gauge,

FIG. 3 is a perspective view the front of the illustrated embodiment showing a flexible inlet tube connected to a radiator,

FIG. 4 is a perspective view from the front of the illustrated embodiment of this invention showing the flexible inlet tube connected to a restriction aperture for calibration,

FIG 5 is a perspective view from a second side showing the exhaust aperture of the air pump, and of access ports to the filter, and

FIG 6 shows details of the display of the pressure gauge, and includes a reference card.

DESCRIPTION OF THE PREFERRED EMBODIMENT

It is to be understood that the dimensions of the features in the drawings are not necessarily to scale and dimensions may have been varied to better illustrate one or more of the features.

The apparatus for testing the extent of blockage of a radiator comprises an air passage way 1 which includes a flexible hose 2. At one end of the flexible hose is a means for coupling 3 to a radiator outlet 4 or inlet 5. The means 3 in the illustrated embodiment takes the form of a rubber elbow sleeve that gives an airtight fit around the outlet 4. A negative pressure is induced in the air passage way 1 by an air pump 6 on actuation of the air pump. The air pump sucks air through radiator inlet 5, then through the plurality of tubes 10 of the core of the radiator, out of the radiator outlet 4, through flexible hose 2 and through the air passage way. A pressure gauge 8 measures pressure of the air passage way, which pressure gauge in this embodiment takes the form of a column of liquid, in communication with the air passage way. A means for adjusting the air pressure or the air flow within the air passage way is provided by a bleed valve 9. The bleed valve 9 being adjustable to allow a greater or lesser amount of air from the atmosphere into the air passage way.

Turning now in more detail to the illustrated embodiment. The apparatus is conveniently housed in a sheet metal housing 11 , with suitable frame member supports. The air passage 1 way is conveniently made of a plastics tubing such as PVC. An inlet aperture 12 of the air passage way is mounted to the front of the housing and an inlet proximal portion of the air passage way 13 extends from the inlet aperture to a filter 14.

The filter is conveniently provided to filter out paniculate matter of greater than, for example, approximately 1 mm in size and could take the form of a plastics mesh. The filter housing is mounted onto the side of a housing, and includes a cap 15 , accessible from the outside of the housing , so that the filter may be removed, if desired or necessary for cleaning purposes. The filter housing also includes a moisture sensor, in this embodiment, (but not illustrated) taking the form of two contacts, so that when excess moisture is present, the air pump is cut out.

Between the air filter 14 and the air pump 6 is an inlet distal portion 16 of the air passage way. Extending from the inlet distal portion 16 of the air passageway is a bleed tube 17 communicating between the air passage way 1 and the atmosphere. The open end of the bleed tube is within the housing. The bleed valve 9 is located within the bleed tube 17 and is actuabie by a cock 17a. The cock 17a is mounted to the housing, and extends therethrough, so that it can be operated from the front of the housing. The bleed valve can be used to allow varying amounts of air in from the atmosphere so as to adjust the degree of air flow through the air passage way.

It is to be understood that other means of adjusting the air flow or air pressure through the air passage way might be employed, and thus it might be possible to employ a variable diameter section of tubing in the air passage way, as a means of varying the degree of air flow in the air passage way.

Also communicating with the inlet distal portion 16 of the air passage way is the gauge 8. The gauge comprises a glass tube 18 connected by a flexible hose 19 to a fluid reservoir 20 below the tube 18. The tube 18 has an overflow reservoir 21 above it, so that if excessive suction is applied, indicator fluid does not immediately spill into the air passage way. A gauge hose 22 communicates between the overflow reservoir and the inlet distal portion 16 of the air passage way at a gauge hose inlet 23. The gauge hose inlet is connected with the air passage way some distance from the bleed tube 18, so that turbulence created by the inflow of air through the bleed tube does not cause unworkable fluctuations in the air pressure being measured.

It may be preferred to have the gauge hose inlet 23 positioned before the bleed tube so that measurement of pressure only include air that flows through the radiator core being measured. Furthermore the bleed tube can be positioned much closer to the air pump, leaving a greater length of air passage way, without turbulence effectors within which to place the pressure gauge tube inlet 23.

A window 25 through the housing allows for easy inspection of the level of fluid in the fluid reservoir, so that where appropriate extra indicator fluid can be added.

A liquid sensor is positioned in the overflow reservoir 21 , so that if excessive negative pressure is built up and pressure indicator fluid enters the reservoir 21 , the air pump can be shut down, so that liquid does not spill into the air passage way and the air pump.

The air pump 6 is coupled to an electric motor 24 the latter being positioned directly beneath it. The motor and the pump are supported by a frame of the housing. An outlet of the air pump 26 communicates with an outlet tube 26a extending through the side of the housing and ending in a blowhole 27.

An electronically operated control box 28 is provided to control the components of the radiator blockage tester.

A scale 29 is fixed adjacent to the glass tube 18 of the air pressure gauge 8. The scale is fixed to the housing, and includes at least one calibration reference point 30. A reference card 31 can be inserted into a card holder 32 located on the other side of the glass tube 18. This has markings indicative of various degrees of blockage. The use of the reference card and the scale will be described in somewhat more detail below.

Two casings are supported by the housing, and at an inside end of each of the two casings is provided a respective restriction aperture 33 and 34. The restriction apertures are of a smaller diameter than the flexible tube 2, and are each of a different size to cater for radiators of differing core dimensions.

Because the extent to which the air pump creates negative pressure varies, the extent to which air pressure is created within the air passage way is calibrated to a reference point before use of the apparatus for testing. The length of the fluid column is not sufficient to allow for measurement of the performance of all radiators on the one column and thus calibration can be made when the flexible hose is attached to one of the two casings having alternate sized restriction apertures 33 and 34.

The calibration takes place whilst the flexible hose is attached to one of the casings, as is seen in Fig. 4. The air pump is actuated and the cock 18 is adjusted until the indicator fluid reaches reference level 30. A given type of radiator in its unblocked form will show a reading which is either higher or lower than the reference point. On checking one type of radiator for blockage reference can be made to the reading expected from a standard chart and compared with the reading achieved.

Alternatively for simplicity of use the reference card 31 can be used. The air pressure could be, if desired, calibrated to a reference point 30 shown on the card. Each card is specific for one radiator and thus each card will have individual markings indicating varying degrees of blockage. Thus the lower band 35 shown could correspond to a blockage of between 1 and 5 % the second band 36 could for example correspond to a blockage of between 6 and 10 %, and the third band 37 could correspond to a blockage of greater than10%. Depending upon the amount of blockage, the radiator may need to be flushed, or otherwise cleaned, or simply recored or replaced.

By use of the illustrated method and apparatus the radiator need not be removed from the vehicle, but simply disconnected and drained, and dried out. When used in situ it may be desirable to connect the apparatus up with the radiator to be tested, and have the air pump blow air through the radiator and the air passage way, so as to dry out the radiator before testing. As can be appreciated the use of the illustrated apparatus and method is therefore simple.

The illustrated embodiment provides for a very sensitive and reliable means for measuring air pressure. It is to be understood however that other means to measure air pressure can be provided, and several gauges for air pressure are known, and their suitability for use with this method and apparatus could be tested. Alternatively a gauge for air flow such as a wheel having vanes secured to an axle transverse to the direction of air flow such that the vanes drive the wheel at a rate proportional to the air flow can be used. A rotary cable could be connected with a display driven by the rotation of the cable. An appropriate reference point could be provided on the display, even where the display takes the form of a dial

It is to be understood that the attachment of flexible tube 2 to that side of the radiator core including a second aperture such as may be provided in the illustrated embodiment at the upper portion of the radiator the two apertures designated 5 and 5a in the drawings, the apparatus would not give an accurate measure unless one of the openings 5a were capped because the core of the radiator is not effectively in line with the air passage way.

Claims

1. A method of testing for blockage of a radiator including the step of placing the radiator core in communication with an air passage way (1), the step of effecting an flow of air through the air passage way and the step of measuring the pressure or air flow within the air passage way.

2. A method of testing for blockage of a radiator as in claim 1 wherein the air flow or air pressure is adjusted by an adjustment means to a reference air flow or pressure before the step of placing the radiator core in communication with an air passage way.

3. A method of testing for blockage of a radiator as in claim 2 wherein a restriction (33 or 34) is placed on the air passage way during the step of adjusting the air pressure or flow rate.

4. A method of testing for blockage of a radiator as in any one of the preceding claims wherein there is provided a means to display (8) the measured air pressure or air flow and an indicator means (31 ) for one type of radiator, said indicator means bearing indicia indicative of the degree of blockage of the said one type of radiator, said method including the step of holding the indicator means in juxtaposition to the display and determining the extent of blockage of the radiator being tested.

5. A method of testing for blockage of a radiator as in any one of the preceding claims wherein the method includes the steps of inducing a negative air pressure in the air passage way, and the step of measuring the air pressure.

6. An apparatus for testing the extent of blockage of a radiator, including connector means (3 and 4) to connect the core of a radiator to an air passage way (1), an air pump means (6) for creating an air flow or air pressure within the air passage way, and gauge means (8) to measure and display the air flow or air pressure within the air passage way.

7. An apparatus for testing the extent of blockage of a radiator wherein the air pump means (6) is positioned downstream of the radiator, and the gauge means (8) is positioned between the air pump and the radiator.

8 An apparatus for testing the extent of blockage of a radiator as in either claim 6 or 7 including adjustment means (9) to adjust the air flow or air pressure within the air passage way.

9 An apparatus for testing the extent of blockage of a radiator wherein the adjustment means (9) is a bleed valve, connected to the air passage way between the connector means (3 and 4) and the air pump (6).

10 A method for testing the extent of blockage of a radiator substantially as hereinbefore described with reference to the drawings.

11 An apparatus for testing the extent of blockage of a radiator substantially as hereinbefore described with reference to the drawings.