Heat Exchanger

This application claims priority to European Patent Application No. 24181472.2 filed Jun. 11, 2024, the entire contents of which are hereby incorporated by reference herein.

The present disclosure relates to heat exchangers and a method of manufacturing heat exchangers.

In one example of an embodiment, a heat exchanger includes a working fluid inlet configured to receive a working fluid, a working fluid outlet in fluid communication with the working fluid inlet, a coolant inlet configured to receive a coolant, a coolant outlet in fluid communication with the coolant inlet, a first plate, a second plate stacked on the first plate to define a working fluid channel between the first plate and the second plate, a third plate stacked on the second plate to define a coolant channel between the second plate and the third plate, a fourth plate stacked on the third plate, and a reinforcement plate positioned in the coolant channel. The working fluid channel provides fluid communication of the working fluid between the working fluid inlet and the working fluid outlet. The coolant channel provides fluid communication of the coolant between the coolant inlet and the coolant outlet. The coolant is configured to reduce a temperature of the working fluid as the coolant flows through the coolant channel. The working fluid channel is further defined between the third plate and the fourth plate. The reinforcement plate includes a first surface and a second surface opposite the first surface. The first surface is brazed to the second plate. The second surface is brazed to the third plate.

Other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings.

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.

illustrates a heat exchanger. In one embodiment, the heat exchangeris a vehicle oil cooler and more particularly a stacked plate vehicle oil cooler. The heat exchangeris coupled to a housing(also referred to as a shell). The housingsupports the heat exchangerand facilitates a flow of fluids through the heat exchanger. The housingis coupled to an engine block. The engine blockhouses an engine, which is lubricated by a first fluid (also referred to as a working fluid). In the illustrated embodiment, the first fluid is motor oil. In other embodiments, the first fluid can be, for example, exhaust gas. During operation of the engine, the engine heats (i.e., rises in temperature), which causes the oil to also heat. The heat exchangercools (i.e., decrease the temperature of) the oil, which is described in further detail below.

With reference now to, the heat exchangeris illustrated in greater detail. The heat exchangeris positioned within a cavitydefined by the housingand the engine block. The cavityis filled with a second fluid. The second fluid is a coolant. The coolant can be, for example, ethylene glycol, propylene glycol, etc. The coolant is configured to cool the oil. The heat exchangerincludes a base plateand heat exchanger platesstacked on the base plate. In one embodiment, the base and heat exchanger plates,are formed from stainless steel. In other embodiments, the base and heat exchanger plates,can be composed of another suitable material (e.g., cast iron, aluminum, etc.). In the illustrated embodiment, the base plateis coupled to the housingby fasteners(shown in). The fastenerscan be bolts, screws, or any other suitable fastener. Each fastenerextends through an associated base aperturein the base plate(shown in). The base platecan alternatively be coupled to the housing(or alternatively to the engine block) by any suitable method (e.g., welding, brazing, etc.).

As illustrated in, the base plateincludes a first inlet(also referred to as a working fluid inletor an oil inlet) and a first outlet(also referred to as a working fluid outletor an oil outlet) in fluid communication with and downstream from the oil inlet. The oil inletdefines an entrance into an inlet manifold. The inlet manifoldis a generally cylindrical recess that extends through the base plateand the heat exchanger plates. The oil outletdefines an exit from an outlet manifold. The outlet manifoldis a generally cylindrical recess that extends through the base plateand the heat exchanger plates. The oil flows into the heat exchangerthrough the inlet manifoldand out of the heat exchangerthrough the outlet manifold.

With continued reference to, the heat exchanger platesinclude a first plateand a second plate. The first plateis coupled to the base plateand the second plateis stacked on the first plate. The first and second plates,each include a first apertureand a second aperture. Each first apertureis aligned with the oil inletof the base plate. The first aperturesfurther define the inlet manifold. Each second apertureis aligned with the oil outletof the base plate. The second aperturesfurther define the outlet manifold.

The first plateand the second plateare coupled together and define a first fluid channel(also referred to as a working fluid channelor an oil channel) therebetween. The oil channelis further defined by the inlet manifoldand the outlet manifold. The oil flows through the oil channel. More specifically, the oil is configured to flow from the inlet manifold, between the first and second plates,, and out the outlet manifold. The oil is configured to be cooled as the oil flows through the oil channel. Relatively warm oil passes into the heat exchangerthrough the inlet manifold, flows through the oil channel, and relatively cool oil exits the heat exchangervia the outlet manifold. In some embodiments, turbulators or fins are located in the oil channel. The turbulators provide turbulence to the flow of the oil within the oil channelto increase heat transfer between the oil and coolant.

In some examples of embodiments, the heat exchangermay not include a first plate. In these embodiments, the second platecan be coupled directly to the base plate. The oil channelis then defined between the base plateand the second plate. In these embodiments, the base platecan alternatively be referred to as a first plate.

With continued reference to, the heat exchanger platesincludes a third plate. The third plateis stacked on the second plate. More specifically, the second plateincludes first dimples, and the third plateincludes second dimples. Each first dimpleextends from the second platein a direction toward the third plate. Each second dimpleextends from the third platein a direction toward the second plate. Each first dimpleengages one respective second dimple. More specifically, the first and second dimples,are coupled together.

The second and third plates,define a second fluid channel(also referred to as a coolant channel) therebetween. As such, the first and second dimples,extend into the coolant channel. The coolant channelis further defined by the cavity. The coolant flows through the coolant channel. More specifically, the coolant flows into the cavity, between the second and third plates,, and then out of the cavity. The coolant cools (i.e., decreases a temperature of) the oil within the oil channelwhen the coolant flows between the second and third plates,.

The heat exchanger platesfurther includes a fourth plate. The fourth plateis stacked on the third plate. The third and fourth plates,are coupled together and further define the oil channeltherebetween. As such, the oil is configured to flow from the oil inlet, between third and fourth plates,, and out the oil outlet.

The heat exchanger platesfurther includes a fifth plate. The fifth plateis stacked on the fourth plate. More specifically, the fourth plateincludes third dimples, and the fifth plateincludes fourth dimples. Each third dimpleengages and is coupled to one respective fourth dimple. The third and fourth dimples,have the same features as the first and second dimples,, respectively. As such, any feature or function described with reference to the first and second dimples,can apply to the third and fourth dimples,and any other dimple on the heat exchanger.

The heat exchanger platesfurther includes a sixth plate. The sixth plateis stacked on the fifth plate. The fifth and sixth plates,are coupled together and further define the oil channeltherebetween. As such, the oil flows from the oil inlet, between fifth and sixth plates,, and out the oil outlet.

Similar to the first and second plates,, the third, fourth, fifth, and sixth plates,,,include the first and second apertures,that further define the inlet and outlet manifolds,, respectively.

The first and second plates,can be referred to as a first plate pair, the third and fourth plates,can be referred to as a second plate pair, and the fifth and sixth plates,can be referred to as a third plate pair. In the illustrated embodiment, the first, second, and third plate pairs are identical except for the first platenot including any dimples. In the illustrated embodiment, the heat exchangerincludes twelve plate pairs. In other embodiments, the heat exchangercan include any suitable number of plate pairs. The oil flows within the plate pairs (i.e., through the oil channel), and the coolant flows between the plate pairs (i.e., through the coolant channel).

With reference now to, the heat exchangerincludes a reinforcement plate. During operation, the heat exchangercan receive high stresses due to vibration caused by the motor. Accordingly, the reinforcement plateincreases the strength of the heat exchangerto prevent failure in high stress areas. As best illustrated in, the reinforcement platedefines a first surface(shown in), a second surfaceopposite the first surface, and an outer surface(also referred to as an outer edge) extending between the first surfaceand the second surface. The illustrated first surfaceis coupled to the second plate, and the illustrated second surfaceis coupled to the third plate(shown in).

The reinforcement plateincludes a plate aperture. The plate apertureextends through the first surfaceand the second surfaceand is spaced from the outer surface. The plate apertureis sized to receive one first dimpleand one second dimple(shown in). As such, the plate aperturecan have the same size (e.g., diameter) or a greater size than the respective first and second dimples,. The reinforcement plateis secured in place by the plate aperture. The first and second dimples,extending through the plate apertureprevent the reinforcement platefrom moving throughout the oil channel. In the illustrated embodiment, the reinforcement plateincludes one plate aperture. In other embodiments, the reinforcement platecan include more than one plate aperture(e.g., two, three, etc.). In these embodiments, each plate aperturereceives a pair of dimples.

With continued reference to, the reinforcement plateincludes a notchin the outer surface. The notchextends through the first surface, the second surface, and the outer surface. The illustrated notchis shaped to receive a portion of one first dimpleand a portion of one second dimple(shown in). As such, the notchcan have the same curvature or a greater curvature than the respective first and second dimples,. The reinforcement plateis secured in place by the notch. The first and second dimples,being received in the notchprevent the reinforcement platefrom moving throughout the oil channel. In the illustrated embodiment, the reinforcement plateincludes three notches. Each notchcan have an identical profile or a different profile. Each notchcan extend around the respective first and second dimples,by the same amount or a different amount. In other embodiments, the reinforcement platecan have any suitable number of notches(e.g., one, two, four, etc.).

The second platedefines a first outer edge. The first outer edgeextends in a direction generally perpendicular to an upper surface of the second plate. The reinforcement plateis spaced apart from the first outer edgeby a distance. Axial stresses absorbed by the reinforcement plateare desirably not transferred to the first outer edge. The distancecan be 1 millimeter, 1.5 millimeters, or any other suitable distance to inhibit or minimize stresses being transferred to the first outer edge. The reinforcement plateis spaced apart from a second outer edge (not shown) of the third plateby the distancefor similar reasons as described with reference to the first outer edge.

With returned reference to, the reinforcement platedefines a reinforcement plate area. The reinforcement plate areacan be defined as the area between the outer surface. Each heat exchanger platedefines a heat exchanger area. The heat exchanger areacan be defined as the area between the outer edge (e.g., the first outer edge). The reinforcement plate areais less than the heat exchanger area. More specifically, the reinforcement plate areacan be 25%, 10%, 5%, or less than the heat exchanger area. The ratio of the reinforcement plate areato the heat exchanger areacan be any ratio suitable to best improve the structural integrity of the heat exchanger.

With returned reference to, the heat exchangerincludes reinforcement plates. Each reinforcement plateis positioned in the coolant channel. The coolant contacts each reinforcement plateas the coolant flows through the coolant channel. In the illustrated embodiment, the heat exchangerincludes two reinforcement platesbetween the second and third plates,and two reinforcement platesbetween the fourth and fifth plates,. Between the second and third plates,, one reinforcement plateis positioned adjacent the inlet manifoldand one reinforcement plateis positioned adjacent the outlet manifold. Between the fourth and fifth plates,, one reinforcement plateis positioned adjacent the inlet manifoldand one reinforcement plateis positioned adjacent the outlet manifold. The reinforcement platesadjacent the inlet manifoldare aligned, and the reinforcement platesadjacent the outlet manifoldare aligned. In other embodiments, reinforcement platesbetween different pairs of heat exchanger platescan be offset or misaligned. In other embodiments, the heat exchangercan include any suitable number of reinforcement platesbetween any suitable heat exchanger plates. As one non-limiting example, the heat exchangercan include four reinforcement platesbetween the second and third plates,and two reinforcement platesbetween eighth and ninth plates (not shown). The reinforcement platescan be positioned in any high stress area or areas of the heat exchangerto prevent failure caused by vibrations from the motor.

With reference to, during the manufacturing process, a copper foil frameis placed between each pair of heat exchanger plates. A copper foil frameis placed between the second and third plates,, the fourth and fifth plates,, etc. The copper foil framemelts when the heat exchangeris placed in a braze furnace, which provides a filler metal for brazing and securing the heat exchanger platestogether. Each copper foil framecan extend along the entire respective reinforcement plate. The copper foil frameincludes a bodywith an inlet manifold apertureand an outlet manifold apertureextending through the body. The inlet and outlet manifold apertures,are aligned with the inlet and outlet manifolds,, respectively. The copper foil framecan optionally include void aperturesextending through the body. The void aperturesdecrease the amount of material in the copper foil frame.

With reference now to, the copper foil frameincludes a recessed portion. The recessed portionis recessed relative to the body. The recessed portionis defined by a leading edge(also referred to as a slit) through the copper foil frame. The leading edgeis defined between a pair of connectors. The connectorsare positioned on a periphery of the copper foil frameand connect the recessed portionto the body. The recessed portionincludes a foil aperture.

With reference to, the foil aperturereceives a first dimple. In the illustrated embodiment, the recessed portionincludes four foil apertures. Each foil aperturereceives one first dimple. The recessed portionengages the upper surface of the second platebecause the first dimplesextend through the foil apertures. The bodyengages the tops of the respective first dimples. The recessed portionis recessed relative to the bodyby a height of the first dimples.

When placing the reinforcement plateon the second plate, the leading edgeof the recessed portionacts as a guide for the reinforcement plate. The leading edgepresents a clear position for the reinforcement plateto be positioned. Because the bodyrests upon the first dimples, and the recessed portionrests upon the top surface of the second plate, the reinforcement plateis only able to engage the first dimplesthat extend though the foil apertures. This improves the accuracy of the position of the reinforcement plateon the second plate.

The illustrated copper foil frameincludes one recessed portion. In other embodiments, the copper foil framecan include any suitable number of recessed portions. For example, the copper foil framecan include a number of recessed portionsthat is equal to the number of reinforcement platesadjacent that copper foil frame. Once the reinforcement plateis positioned in the recessed portion, additional heat exchanger platescan be stacked upon the reinforcement plateand the second plate.

With reference to, the third plateis stacked on the second plate, and the fourth plateis stacked on the third plate. As best illustrated in, the reinforcement plateengages the two adjacent heat exchanger plates. In the illustrated embodiment, the reinforcement plateengages the second plateand the third plate. The copper foil frameis positioned between the reinforcement plateand the second plateand/or the third plateyet the reinforcement plateis still considered to engage the second or third plate,. Following the brazing operation, the reinforcement platewill be coupled to the second plateand the third platedue to the copper foil framemelting and then hardening.

With reference to, the heat exchangercan include a spacer plate. During operation, the heat exchangercan receive high stresses due to vibration caused by the motor. Accordingly, the spacer plateincreases the strength of the heat exchangerto prevent failure in high stress areas. The spacer plateis positioned between the base plateand the first plate. The spacer plateis coupled to the base plateand the first plate. The spacer plateincludes a first spacer aperture, which further defines the inlet manifold.

With continued reference to, the base plateincludes a first projectionto retain the reinforcement plate. The first projectionis an annular projectionthat further defines the inlet manifold. The first projectionextends from the base platein a direction toward the first plate. The first projectionis received by the first spacer aperture. When placing the spacer plateon the base plate, the first projectioncan act as a guide for the spacer plate.

With reference to, the spacer plateincludes a second spacer aperture, which further defines the outlet manifold. The base plateincludes a second projectionto retain the reinforcement plate. The second projectionis an annular projectionthat further defines the outlet manifold. The second projectionextends from the base platein a direction toward the first plate. The second projectionis received by the second spacer aperture. When placing the spacer plateon the base plate, the second projectioncan act as a guide for the spacer plate.

With continued reference to, the spacer plateextends along a majority of the base plate. In other embodiments, the spacer platecan have any suitable shape to improve the strength of the heat exchanger. In some embodiments, the heat exchangercan include the spacer platein combination with one or more reinforcement plates. In other embodiments, the heat exchangercan include either the spacer plateor one or more reinforcement plates.

During operation, relatively warm oil flows from the motor and into the inlet manifoldthrough the oil inlet. The warm oil then flows through the plate pairs (e.g., the first and second plates,, the third and fourth plates,, the fifth and sixth plates,, etc.) in a direction towards the outlet manifold. The coolant flows between the plate pairs throughout the coolant channel. The coolant absorbs heat from the oil. The coolant reduces a temperature of the oil, which causes the temperature of the oil to decrease and the temperature of the coolant to increase. Once the oil flows into the outlet manifold, the oil is relatively cool. The oil then flows out of the outlet manifoldthrough the oil outletand returns into the engine. In some examples of embodiments, the coolant can be removed from the cavityto be cooled. The coolant is cooler than the oil, such that the oil can dissipate heat to be absorbed by the coolant.

Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the invention as described. Various features and advantages of the invention are set forth in the following claims.