EP3580458A1

EP3580458A1 - Device for testing the temperature resistance of a pump

Info

Publication number: EP3580458A1
Application number: EP18703774.2A
Authority: EP
Inventors: Pascal Romano
Original assignee: Supratec SA
Current assignee: Supratec SA
Priority date: 2017-02-07
Filing date: 2018-02-06
Publication date: 2019-12-18
Also published as: WO2018146100A1; FR3062686B1; FR3062686A1

Abstract

A device for testing the temperature resistance of a pump, comprising a main circuit that is provided with means for connecting to the pump to be tested and is intended to contain a test fluid, the main circuit being connected: - by at least one first valve to a first heat exchanger connected to a first secondary circuit carrying a first heat transfer fluid, the first secondary circuit being associated with first means for maintaining the first secondary fluid at a first predetermined temperature; - by at least one second valve to a second heat exchanger connected to a second secondary circuit carrying a second heat transfer fluid, the second secondary circuit being associated with second means for maintaining the second secondary fluid at a second predetermined temperature.

Description

DEVICE FOR TESTING THE TEMPERATURE OF A PUMP

The present invention relates to methods for testing the temperature resistance of a pump, in particular a cooling circuit of a motor vehicle engine.

BACKGROUND OF THE INVENTION

A pump is a known device for aspirating and discharging a fluid to move the fluid from one point to another, for example to circulate in a circuit.

For this purpose, a pump comprises a variable volume chamber having a liquid inlet port and a liquid outlet port, and at least one movable member for causing the volume of the chamber to vary. Piston pumps, centrifugal pumps and also peristaltic pumps are thus known.

The moving parts of pumps are now often powered by an electric motor. They can also be operated mechanically. This is particularly the case of the water pump of the cooling circuit of a motor vehicle which is driven generally by the timing belt.

This type of pump sucks and delivers a coolant called coolant which, as its name suggests, is intended to cool the engine. Indeed, an engine sees its temperature climb as it rotates. The coolant in contact with the engine block then rises in temperature at the same time as this one. The cooling circuit includes a heat exchanger in which the coolant is cooled before returning to the engine block to cool it in turn and maintain it at an optimum operating temperature. This temperature is about 90 ° C in the case of a heat engine.

Beyond 100 ° C, some parts of the engine begin to degrade. The malfunction of such a water pump will then irreparably cause overheating of the engine block causing damage that can go to the breakage of the engine. Thus, a failure of the pump can cause damage whose cost is much higher than the cost of the pump itself.

It is therefore essential that this type of water pump is endurance and withstands significant temperature variations of the aspirated fluid.

Indeed, if an engine reaches after a few kilometers its optimal temperature of performance (90 ° C), it is not uncommon that at the start its temperature is negative, especially in winter during a prolonged parking. The coolant will therefore move very rapidly from a negative temperature to a temperature of almost 100 ° C.

Therefore, for obvious reasons of reliability, it is important to be able to test the temperature resistance of this type of pump before marketing.

However, performing tests in real conditions is complex and expensive to implement. Moreover, it does not make it possible to vary the temperature of the coolant on demand, or even to maintain it at a determined temperature other than that of the optimal engine efficiency achieved in just a few minutes.

OBJECT OF THE INVENTION

An object of the invention is therefore to provide a device for testing the temperature resistance of a pump. PRESENTATION OF THE INVENTION

With a view to achieving this object, the invention proposes a device for testing the temperature resistance of a pump comprising a main circuit which is provided with connection means to the pump to be tested and which is intended to contain a fluid test.

The main circuit is connected by at least a first valve to a first heat exchanger, itself connected to a first secondary circuit carrying a first coolant secondary fluid. This first secondary circuit is associated with first means for maintaining the first secondary fluid at a first predetermined temperature.

The main circuit is also connected by at least one second valve to a second heat exchanger, itself connected to a second secondary circuit carrying a second secondary heat transfer fluid. This second secondary circuit is associated with second means for maintaining the second secondary fluid at a second predetermined temperature.

Thus, the test fluid is preferably the coolant with which the pump is intended to operate in nominal use. The first secondary fluid is selected to have optimal behavior at the first predetermined temperature and the second secondary fluid is selected to have optimal behavior at the second predetermined temperature. For example, in the case where the second predetermined temperature is much lower than 0 ° C, a secondary fluid will be chosen as a fluid that will not form crystals at this temperature so as not to risk clogging the second secondary circuit and in particular the second heat exchanger. In the case where the first predetermined temperature is much higher than 0 ° C, one will choose as the first secondary fluid a fluid that does not degrade in the long term at this temperature. Since the first and second secondary fluids do not have to have optimum properties over the entire temperature range, they are less expensive than the test fluid and, because of the use of the first and second secondary fluids, the necessary amount of Test fluid is relatively weak.

Advantageously, the connection valves of the main circuit to the first and second heat exchangers are proportional type.

In this way, the test fluid passing through the pump can be maintained at a predetermined temperature by regulating its passage through the first and second heat exchangers.

In the context of the invention, it is also possible to vary the temperature of the test fluid rapidly by appropriately actuating the various valves of the device, which will have the effect of accelerating the aging of the pump and thus reducing the test time.

It should be noted that a significant temperature difference between the test fluid and the secondary fluids allows optimal performance of the heat exchangers, and thus makes it possible to accelerate the temperature variation of the test fluid.

In the case where it is desired to bring the test fluid to a temperature close to the limits of its operating range, the use of a secondary fluid different from the test fluid is particularly advantageous for the proper functioning of the device.

According to another embodiment of the invention, the secondary circuits are connected to the heat exchangers by at least one valve.

It should be noted that, for reasons of reliability, it is advisable to test at temperature a pump with a test fluid whose temperature is higher (or lower) than that of normal conditions of use. The consequences of a malfunction of a pump may be such that a sizing of the pump can not always be accepted.

According to a particular characteristic, the first means of temperature maintenance comprise a hot group arranged to maintain the first fluid at a temperature above 100 ° C and, preferably, 130 ° C.

This embodiment of the invention makes it possible, for example, to recreate the temperatures in which a motor vehicle cooling circuit pump operates in very hot weather.

According to another particular characteristic, the second temperature holding means comprise a cold group arranged to maintain the second fluid at a temperature below 0 ° C and preferably - 40 ° C.

This embodiment of the invention makes it possible to recreate, for example, the temperatures in which a motor vehicle cooling circuit pump operates after prolonged parking of a vehicle in winter.

According to a preferred embodiment of the invention, the temperature of at least one of the heat transfer fluids of the secondary circuits results from the use of a cold unit having a temperature of around -25 ° C. combined with Peltier modules having a temperature around -40 ° C.

According to another embodiment, the main circuit is connected, by at least one third valve, to a third heat exchanger connected to a third secondary circuit carrying a third heat transfer secondary fluid. This third circuit secondary is associated with third means for maintaining the third secondary fluid at a third predetermined temperature.

Advantageously, this third secondary circuit is connected to a heat exchanger connected to the second secondary circuit.

The invention also has o o jet a method of verifying the temperature resistance of a pump of a cooling circuit of a motor vehicle engine by means of a test device of the aforementioned type, comprising the steps connecting the pump to the device and controlling the valves in a predetermined sequence to cause a succession of changes in the temperature of the test fluid.

DESCRIPTION OF THE FIGURES

The invention will be better understood in the light of the description which follows, which is purely illustrative and nonlimiting, and should be read with reference to the appended figures among which:

FIG. 1 represents a block diagram of a test device according to a first embodiment of the invention;

- Figure 2 is similar to Figure 1 and shows a test device according to a second embodiment of the invention;

- Figure 3 is similar to Figure 1 and shows a test device according to a third embodiment of the invention;

FIG. 4 is a block diagram of a Peltier thermal block. DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, the test device illustrated in FIG. 1 is intended to check the temperature resistance of a pump P.

For this purpose, the test device comprises a main circuit 1 containing a test fluid 2, a first secondary circuit 10 in which circulates a secondary fluid 12, a second secondary circuit 20 in which a secondary fluid 22 circulates, and a third secondary circuit 30 in which circulates a secondary fluid 32. The fluids 12, 22, 32 are heat transfer fluids, and here the fluid 2.

The main circuit 1 comprises a main loop having ends provided with connector for connection to the pump P and to a valve 4. It comprises:

a first section 1.1 provided with a first heat exchanger 13 and a first valve 14;

a second section 1.2 provided with a second heat exchanger 23 and a second valve 24; - A third section 1.3 provided with a third heat exchanger 33 and a third valve 34. The sections 1.1, 1.2, 1.3 are connected to the main loop of the main circuit 1 on either side of the inputs-outputs of the 4. Figure 1 thus illustrates a parallel arrangement of the first section 1.1, the second section 1.2 and the third section 1.3. Although not illustrated, a serial arrangement of these sections is also possible.

The valves 14, 24, 34 are respectively upstream of the heat exchangers 13, 23, 33 so as to isolate each section 1.1, 1.2, 1.3 of the main circuit 1 against each other. Conversely, the valve 4 makes it possible to force the test fluid to circulate in sections 1.1, 1.2, 1.3 whose valves 14, 24, 34 are open. Thus, to circulate the test fluid through the heat exchanger 13 of the first section 1.1, it is necessary to close the valves 4, 24 and 34 and to open the valve 14 of the first section 1.1.

In the same way, to circulate the test fluid through the heat exchanger 23 of the second section 1.2, it is necessary to close the valves 4, 14 and 34 and to open the valve 24 of the second section 1.2; and to circulate the entire test fluid through the heat exchanger 33 of the third section 1.3, it is necessary to close the valves 4, 14 and 24 and to open the valve 34 of the third section 1.3.

It will obviously be possible to circulate the test fluid simultaneously in several sections by appropriately opening and closing the valves 4, 14, 24, 34: for example, to circulate the test fluid simultaneously in the first and second heat exchangers. opening the valves 14 and 24.

If, on the other hand, it is not desired to circulate the test fluid in the heat exchangers 13, 23, 33, the valves 14, 24 and 34 will then be closed, taking care that the valve 4 is in the open position in order not to create, under the action of the pump P, an overpressure in the main circuit can significantly damage the device if it is not provided with appropriate security.

The first secondary circuit 10 is connected to the first heat exchanger 13, the second secondary circuit 20 is connected to the second heat exchanger 23, and the third secondary circuit 30 is connected to the third heat exchanger 33.

The first secondary circuit 10 is associated with temperature holding means 15 for maintaining the secondary fluid 12 at a predetermined temperature T1. The second secondary circuit 20 is associated with temperature holding means 25 for maintaining the secondary fluid 22 at a predetermined temperature T2.

The third secondary circuit 30 is associated with temperature holding means 35 for maintaining the secondary fluid 32 at a predetermined temperature T3.

According to a preferred version of the invention, the temperature holding means 15 of the first secondary circuit 10 comprises a hot group enabling the secondary fluid 12 and then the test fluid 2 to reach at least 100 ° C., and preferably 130 ° C. .

The means 25 for maintaining the temperature of the second secondary circuit 20 comprises a cold unit enabling the secondary fluid 22 and then the test fluid 2 to reach a temperature below 0 ° C. and here a temperature of -25 ° C.

The means for maintaining the temperature of the third secondary circuit 30 comprises a cold unit enabling the secondary fluid 32 and then the test fluid 2 to reach a temperature of preferably -40 ° C. To limit the cost and the bulk of this cold unit, it is intended to exploit the temperature of -25 ° C of the secondary fluid 22. For this purpose, the cold group of the temperature holding means 35, shown in FIG. 4, comprises a thermal block, generally designated 50, comprising Peltier modules 51 exploiting the thermoelectric effect or Peltier effect. These modules 51 are juxtaposed between two exchangers 52, 53 in which countercurrent flow the second secondary fluid 22 and the third secondary fluid 32 respectively (Figure 3). The heat exchanger 52 of the heat block 50 is thus connected to the second secondary circuit 20 to circulate the second secondary fluid 22 and the heat exchanger 53 of the heat block 50 is connected to the third secondary circuit 30 to circulate the third fluid secondary 32. The operating principle of PELTIER modules 51 is known in itself and will not be more detailed here.

Thus, such a device makes it possible to circulate in the main circuit, and thus in the pump P, a test fluid 2 whose temperature can be maintained by regulating its passage through the heat exchangers 13, 23 and 33 via valves 4, 14, 24 and 34.

The valves 4, 14, 24 and 34 are proportional type here. They make it possible to control the flow rate of the fluid passing through them and thus to regulate more easily the heat exchanges between the test fluid 2 and the secondary fluids 12, 22 and 32 of the secondary circuits 10, 20, 30.

Advantageously, the secondary circuits 10, 20 and 30 are connected to the heat exchangers 13, 23 and 33 by valves 16, 26 and 36. The control of heat exchange between the main circuit 1 and the secondary circuits 10, 20, 30 is then improved.

By cleverly manipulating the various valves equipping the device of the invention, it will be easy to cool or heat the test fluid 2 so as to vary its temperature in a range and for a preset time. Preferably, the test fluid 2 will be successively brought to each of the temperatures T1, T2, T3 in a sequence and for predefined times to correspond to conditions to which the pump in use is subjected, here a vehicle cooling circuit pump. automobile as an example. At each start following a prolonged stop, the coolant passes in just a few minutes from the ambient temperature to the optimum engine performance temperature. The device proposed by the invention thus makes it possible to test a cooling circuit pump by varying the temperature of the fluid passing through it from -40 ° C to 130 ° C in a predefined time, for example two minutes.

Elements identical or similar to those previously described will have the same numerals increased by one hundred for the second embodiment shown in Figure 2 and increased by two hundred for the third embodiment of Figure 3.

With reference to FIG. 2, and as before, the device according to the second embodiment comprises a main circuit 101 which comprises a main loop having ends provided with a connection connector to the pump P and to a valve 104. It comprises:

a first section 101.1 provided with a first heat exchanger 113 and a first valve 114;

a second section 101.2 provided with a second heat exchanger 123 and a second valve

124;

a third section 101.3 provided with a third heat exchanger 133 and a third valve 134.

The first secondary circuit 110 is associated with temperature holding means 115 for maintaining the secondary fluid 112 at a predetermined temperature T1.

The second secondary circuit 120 is associated with temperature holding means 125 for maintaining the secondary fluid 122 at a predetermined temperature T2.

The third secondary circuit 130 is associated with temperature holding means 135 for maintaining the secondary fluid 132 at a predetermined temperature T3.

Unlike the first embodiment, the second secondary circuit 120 and the third circuit secondary are not connected to one thermal block. The temperature maintaining means 135 comprise a conventional cold unit arranged to bring the secondary fluid 132 directly from the ambient temperature to a temperature of around -40 ° C. This cold group is nevertheless relatively expensive and cumbersome.

With reference to FIG. 3, and as before, the device according to the third embodiment comprises a main circuit 201 which comprises a main loop having ends provided with connector for connection to the pump P, to a valve 204.1 and to a valve 204.2. He understands :

a first section 201.1 provided with a first heat exchanger 213 and a first valve 214;

a second section 201.2 provided with a second heat exchanger 223 and a second valve 224.

The sections 201.1 and 201.2 are connected to the main loop of the main circuit 201 on either side of the inputs-outputs of the valves 204.1 and 204.2 respectively.

The first secondary circuit 210 is associated with temperature holding means 215 for maintaining the secondary fluid 212 at a predetermined temperature T1.

The second secondary circuit 220 is associated with temperature holding means 225 for maintaining the secondary fluid 222 at a predetermined temperature T2.

Note that there is no third secondary circuit so that the pump P can be tested for two temperatures.

The invention is of course not limited to what has just been described, but on the contrary covers any variant within the scope defined by the claims. The means for maintaining the temperature may in particular be arranged to allow temperatures different from those mentioned.

The temperature maintaining means may also be arranged to maintain the secondary fluids at a temperature much lower or higher than that at which it is desired to bring the test fluid.

Alternatively, the device according to the invention may comprise temperature holding means comprising either a hot group or a cold group, or two cold groups for example.

The number of secondary circuits can be changed.

Claims

1. A device for testing the temperature resistance of a pump comprising a main circuit which is provided with connection means to the pump to be tested and which is intended to contain a test fluid, the main circuit being connected to:

by at least a first valve with a first heat exchanger connected to a first secondary circuit carrying a first heat transfer fluid, the first secondary circuit being associated with first means for holding the first secondary fluid at a first predetermined temperature,

- By at least a second valve to a second heat exchanger connected to a second secondary circuit carrying a second heat transfer fluid, the second secondary circuit being associated with second holding means of the second secondary fluid at a second predetermined temperature.

2. Test device according to claim 1, wherein the connecting valves of the main circuit to the heat exchangers are proportional type.

3. Test device according to any one of the preceding claims, wherein the secondary circuits are isolated heat exchangers via valves.

4. Test device according to any one of the preceding claims, wherein the first temperature holding means comprise a hot group arranged to maintain the first fluid at a temperature above 100 ° C and preferably 130 ° C about .

5. Test device according to any one of the preceding claims, wherein the second temperature maintaining means comprise a cold group arranged to maintain the second fluid at a temperature of temperature below 0 ° C and preferably -40 ° C.

6. Test device according to one of claims 1 to 3, wherein the temperature of at least one of the heat transfer fluids of the secondary circuits is derived from the use of a cold group of about -25 ° C associated with Peltier modules close to -40 ° C.

7. Test device according to any one of the preceding claims, wherein the main circuit is connected, by at least a third valve, to a third heat exchanger connected to a third secondary circuit carrying a third heat transfer fluid, the third circuit. secondary being associated with third means for maintaining the third secondary fluid at a third predetermined temperature.

8. Test device according to claim 7, wherein the third secondary circuit is connected to a heat exchanger connected to the second secondary circuit.

9. A method for checking the temperature resistance of a pump of a cooling circuit of a motor vehicle engine using a test device according to any one of the preceding claims, comprising the step of controlling the valves. in a predetermined sequence to cause a succession of changes in the temperature of the test fluid while the pump is in operation.