COOLER CORE AND COVER UNIT FOR A HEAT EXCHANGER INSERTED IN AN ENGINE BLOCK OR TRANSMISSION BLOCK OF A MOTOR VEHICLE

The present invention relates in general, in a first aspect, to a cooler core and cover unit for a fluid heat exchanger of an engine, or of a transmission, in which the heat exchanger casing is inserted into the engine block or transmission block of the motor vehicle.

In a second aspect, the present invention relates to a fluid heat exchanger of an engine or of a transmission that includes said cooler core and cover unit and a cavity inserted in the engine block, or transmission block, which is designed to accommodate the cooler core and is capable of being closed by means of said cover. In particular, the present invention relates to a heat exchanger for the exhaust gases of an engine of a motor vehicle that includes a cavity inserted in the engine block of the vehicle and a cooler core and cover unit capable of being mounted in said cavity.

The invention applies especially to exhaust gas recirculation exchangers of an engine ("Exhaust Gas Recirculation Coolers", or EGRC). However, it may also apply to oil recirculation exchangers of a transmission of a vehicle.

Background of the Invention

The principal function of EGRC exchangers is the exchange of heat between exhaust gases and the coolant fluid, in order to cool said gases. Currently, EGRC heat exchangers are widely used in diesel applications, in order to reduce emissions, and are also used in gasoline applications to reduce fuel consumption.

The current configuration of EGRC exchangers on the market is that of a metal heat exchanger with a casing generally manufactured from stainless steel or aluminium. Basically, there are two types of EGR heat exchanger: a first type consists in a casing inside which there is a bundle of parallel pipes for the passage of the exhaust gases, the coolant circulating through the casing outside the pipes, and the second type comprises a series of parallel plates that constitute the heat-exchange surfaces, such that the exhaust gases and the coolant circulate between two plates, in alternate layers.

Exhaust-gas heat exchangers are known in the prior art and are integrated into the motor vehicle. Patent US2017138320A describes EGR heat exchangers of this type provided with a heat-exchange casing inserted or integrated into the engine block of the actual vehicle, through which a coolant fluid, supplied from a pipe likewise integrated into the engine block, circulates. The cooler core of these exchangers is accommodated inside a cavity inserted in the engine block, the opening of which is closed in a leaktight manner by means of a cover. Inlet and outlet pipes for the exhaust gases are coupled to the gas-circulation circuit of the cooler core by means of orifices provided in said cover. The cavity inserted in the engine block and the cover thereof define the heat-exchange casing through which the coolant fluid circulates.

In order to ensure resistance to pressure changes and the thermal shock generated by the temperatures of the gas and of the coolant, the cover that closes the cavity inserted in the engine block for the exchangers mentioned above must be designed with a predetermined thickness in order to withstand these changes and thermal shock. However, this solution increases the weight of the exchanger and also its cost.

Description of the Invention

With a view to solving the problems mentioned, according to a first aspect the present invention provides a cooler core and cover unit for a fluid heat exchanger of an engine or of a transmission, which is characterized in that the cover includes:

- a plate of reduced thickness dimensioned in order to close an opening of a cavity inserted in the engine block, or transmission block, of said motor vehicle, said cavity being capable of accommodating said cooler core,

- a frame for reinforcing said plate, and

- an inlet port and an outlet port for the fluid to be cooled, which can be coupled to the cooler core via said plate or reinforcing frame.

The claimed unit makes it possible to reduce the weight and the cost of prior-art exchangers, since the cavity that receives the cooler core is closed in a leaktight manner by means of a cover that includes a plate of reduced thickness that is reinforced externally by means of a reinforcing frame. The use of heavy covers that are difficult to handle and increase the cost of the final product is thus avoided.

Furthermore, this solution offers the advantage that it is compatible with the use of a gasket that copies the periphery of the opening of the cavity of the engine block or transmission block in order to guarantee optimum leaktightness for the unit.

According to a preferred embodiment, the thickness of the plate is between 0.0004 m and 0.004 m and, advantageously, the reinforcing frame is obtained by moulding using a material selected from a plastics and an aluminium.

Preferably, the reinforcing frame comprises a perimeter structure for reinforcing the periphery of the plate, which ensures optimum leaktightness for the cavity inserted in the engine block, or transmission block, of the motor vehicle.

Advantageously, said reinforcing frame additionally comprises a plurality of partitions extending transversely from one side to the other of said perimeter structure in order to increase the mechanical strength thereof and to protect not only the perimeter of the plate but also the remainder of the surface thereof.

According to the same preferred embodiment, the claimed unit comprises means for securing the reinforcing frame onto the plate during transport of said unit. In this way, the position of the reinforcing frame is secured during transport until the unit is mounted in the cavity inserted in the engine block, or transmission block, of the motor vehicle.

Advantageously, said securing means of the reinforcing fame comprise a plurality of securing lugs provided in the periphery of the plate or, alternatively, in the periphery of the gasket. According to one embodiment, these lugs may be designed such that they extend vertically in the periphery of the plate or of the gasket and each comprise a tab for retaining the frame.

Preferably, the periphery of the plate includes a plurality of orifices for the passage of fastening elements and, advantageously, the frame reinforcing the plate comprises a further plurality of orifices for the passage of said fastening elements that are arranged to correspond with the plurality of orifices of the plate. Once again, advantageously, the gasket comprises a further plurality of orifices for the passage of said fastening elements that are arranged to correspond with the plurality of orifices of the plate and of the frame for reinforcing said plate, in the transport position of the claimed unit.

In this way, the plate, reinforcing frame and gasket unit may be easily and conveniently fastened to the engine block using screws that are screwed into the periphery of the opening of the cavity of the engine block.

As mentioned previously, in addition to the frame and the plate the cover of the claimed unit includes an inlet port and an outlet port for the fluid to be cooled that can be coupled to the cooler core via the plate or, alternatively, via the reinforcing frame. According to one embodiment, these inlet and outlet ports each comprise a fluid inlet or outlet pipe that can be coupled to a fluid inlet or outlet of the cooler core via orifices provided in the plate, and a flange for joining said fluid inlet or outlet pipe to an inlet or outlet pipe for fluids of the motor vehicle.

According to the same embodiment, the cooler core includes a bundle of pipes for the circulation of the fluid to be cooled and is configured such that it can be accommodated inside the cavity inserted in the engine block, or transmission block, said cavity being capable of delimiting the coolant fluid circuit of said bundle of pipes when the unit is in use.

Preferably, the present invention provides an assembled unit wherein the cooler core is coupled to fluid inlet and outlet pipes provided in said plate, and the reinforcing frame is secured to the plate in a predetermined mounting position. The result of this is a unit that is ready for mounting and may be transported easily, ensuring the position of the frame on the plate and the gasket.

According to a second aspect, the present invention provides a heat exchanger for fluids of an engine, especially an exhaust-gas heat exchanger of an engine, which comprises a cooler core and cover unit such as that claimed and a cavity inserted in a block of said engine in order to accommodate the cooler core.

Brief Description of the Figures

For a better understanding of that which has been stated, accompanying drawings schematically and solely by way of non-limiting example show a practical case of embodiment of a cooler core and cover unit for an exhaust-gas heat exchanger of an engine of a motor vehicle.

Figure 1 shows a perspective view of the cavity designed to accommodate the cooler core of the exchanger, which is inserted into the engine block of a motor vehicle.

Figure 2 shows an assembled cooler core and cover unit ready for mounting in the cavity shown in Figure 1 .

Figure 3 shows the unit of Figure 2 assembled and mounted inside the cavity of the engine block of Figure 1 .

Figure 4 is an expanded view of the cooler core and cover unit of Figure 2. Description of a Preferred Embodiment A description is given below, with reference to Figures 1 to 4, of a preferred embodiment of a cooler core and cover unit for a heat exchanger inserted into the engine block of a motor vehicle. This heat exchanger is suitable for cooling the exhaust gases of the engine by means of a coolant fluid.

The cooler core 2 and cover 3 unit 1 claimed, as shown in Figure 2, is designed to be mounted in a cavity 4 inserted in an engine block 5 of a motor vehicle that incorporates the pipes 8 for supplying the coolant fluid. As may be seen in Figure 1 , the cavity 4 of the engine block 5 is provided with an opening 6, the periphery of which includes a plurality of orifices 16a for the screwing-in of screws that allow fastening of the unit 1 and closure of said opening 6 with the cover 3.

The cover 3 of the unit 1 claimed includes:

- a plate 9 of reduced thickness dimensioned in order to close the opening 6 of the cavity 4 inserted in the engine block 5,

- a frame 10 for reinforcing the plate 9, and

- an inlet port 1 1 and an outlet port 12 for the fluid to be cooled, which can be coupled to the cooler core 2 via the plate 9 or the reinforcing frame 10.

In the embodiment described, the cover 3 further includes a gasket 13 that copies the shape of the periphery of the opening 6 of the cavity 4 in order to ensure optimum leaktightness of the cavity 4.

As mentioned in the description of the invention, the claimed unit makes it possible to reduce the weight and the cost of prior-art exchangers, since the plate 9 that closes the cavity 4 inserted in the engine block 5 may be designed with a reduced thickness since it is reinforced externally by means of the reinforcing frame 10. Preferably, the thickness of the plate 9 is between 0.4 mm and 4 mm.

The frame 10 for reinforcing the plate 9 has been designed with a perimeter structure 14 that copies the periphery of the opening 6 of the cavity 4 inserted in the engine block 5, thereby providing the necessary rigidity for the proper functioning of the aforesaid gasket 13. This reinforcing frame 10 may also include a plurality of partitions 15 extending transversely from one side to the other of the perimeter structure 14 in order to increase the mechanical strength of the frame 10 and to protect not only the periphery of the plate 9 but also the remainder of the surface thereof. As may be seen in Figure 4, not only the periphery of the plate 9 but also the periphery of the reinforcing frame 10 and the gasket 13 include a plurality of orifices 16b, 16c, 16d arranged to correspond with the orifices 16a of the periphery of the opening 6 of the cavity 4, when the unit 1 is assembled, in order to allow the passage of screws (not shown) that fasten said unit 1 onto the engine block 5.

The inlet part 1 1 and outlet part 12 for the fluid to be cooled, which also form part of the cover 3, each include a fluid inlet 17 pipe or fluid outlet 18 pipe which can be coupled to a fluid inlet or fluid outlet of the cooler core 2 via an orifice, and a flange 20 for connecting said fluid inlet 17 pipe or fluid outlet 18 pipe to a gas inlet pipe or gas outlet pipe of the motor vehicle.

The cooler core 2 proper includes a bundle of pipes for the circulation of the exhaust gases, which is configured in order to be accommodated inside the cavity 4 inserted in the engine block 5. According to one embodiment, the pipes of the cooler core 2 for the fluid to be cooled may each be formed from two "U"-shape plates. However, other types of pipe configuration would be possible provided these pipes suited the shape of the cavity 4 designed to receive them.

In the embodiment described, the cooler core 2 is coupled to the plate 9 of the cover 3 via respective gas inlet 17 and gas outlet 18 pipes provided in the orifices 19 of said plate 9, whilst the reinforcing frame 10 is secured to the plate 9 in a predetermined mounting position by means of securing lugs 21 extending vertically from the periphery of the gasket 13 (see Figure 4). Each of the securing lugs 21 includes a retaining tab 22 pressure-fitted on the perimeter structure 14 of the reinforcing frame 10.

As mentioned in the description of the invention, the securing lugs 21 fix the assembled position of the cooler core 2 and cover 3 unit 1 , said cover being formed by the plate 9, reinforcing frame 10 and gasket 13, such that the unit 1 is ready for mounting and may easily be transported. By virtue of this, the position of the reinforcing frame 10 on the plate and of the orifices 16b, 16c, 16d provided to allow the passage of the fastening elements is ensured.

Despite the fact that reference has been made to a specific embodiment of the invention, it is obvious for a person skilled in the art that the cooler core 2 and cover 3 unit claimed may undergo numerous changes and modifications and that all the details mentioned may be replaced by other, technically equivalent details without departing from the scope of protection defined by the appended claims. For example, although the description of examples refers to means for securing the reinforcing frame 10 to the plate 9 that are configured as securing lugs 21 , these same securing means could be configured as another type of element, other than the aforesaid lugs, provided that these elements also make it possible to fix the position of the reinforcing frame 10 on the plate 9. Similarly, although the unit 1 example described is for an exhaust-gas exchanger inserted into the engine block 5 of a motor vehicle, said unit 1 claimed would be suitable for an oil-recirculation exchanger of a transmission block of a motor vehicle.