CN215337881U

CN215337881U - Heat exchanger

Info

Publication number: CN215337881U
Application number: CN202023278450.7U
Authority: CN
Inventors: 王铁兵; 周权; 王平; 葛小东; 聂军初
Original assignee: Modine Manufacturing Co
Current assignee: Modine Manufacturing Co
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2021-12-28
Anticipated expiration: 2030-12-29

Abstract

A heat exchanger includes a brazed frame extending around a first fluid passage to braze a perimeter of the first fluid passage and minimize contact between copper and the first fluid. The first fluid passage of the heat exchanger includes a central flow area between the inlet manifold opening and the outlet manifold opening. The brazing frame includes a frame base and a frame wall extending from the frame base at an angle of at least 20 degrees from the base. The frame base includes an inner edge and the frame wall includes an outer edge. The inner edge surrounds and defines the area of the central flow region. The inner edge extends parallel to the outer edge along a perimeter of the first fluid channel, wherein the perimeter is adjacent to the central flow area. The width of the central flow region at its widest point is the separation distance between the inner edge on one side of the frame and the inner edge on the other, opposite side of the frame. The first fluid passage is further defined between a first plate and a second plate brazed together at a perimeter of the first fluid passage by a brazing frame. The third plate is stacked on the second plate to define a second fluid passage between the second plate and the third plate. The first and second fluid channels are fluidly separated, but in thermal contact.

Description

Heat exchanger

Technical Field

The invention relates to a heat exchanger and a method of manufacturing a heat exchanger.

Background

Heat exchangers are known in the art. See, for example, chinese patent ZL201921951482.3, which discloses a heat exchanger that is constructed of a plurality of plates and includes a heat transmitter having smooth side walls. There is still a need for improvement in such heat exchangers to further improve the heat exchange efficiency.

SUMMERY OF THE UTILITY MODEL

The present invention provides a heat exchanger including a first fluid channel in thermal communication with a second fluid channel. The first fluid passage is closed, sealed from the second fluid passage and sealed within the heat exchanger. In particular, the invention provides that the first fluid channel is formed between two plates and is sealed by a braze joint between the two plates, which braze joint is in particular formed by a copper filler material located in particular at the perimeter of the first fluid channel and in contact with the perimeter area of the two plates. Positioning the copper fill material specifically in this area may prevent or minimize contact between the first fluid (typically oil) and the copper material within the first fluid channel, which helps prevent diffusion of the copper material into the first fluid, and may prevent or minimize flow of the copper material into other components of the mechanical system, thereby keeping the first fluid clean and beneficial to the mechanical system. In order to precisely locate such a copper filler material, the invention further provides that the copper filler material is a foil material, in particular a foil brazing frame. The brazing frame is mounted between the two plates at the peripheral corners and edges of the two plates, where the two plates are nested together.

The first fluid channel of the heat exchanger includes a central flow area within a perimeter of the first fluid channel and between the inlet manifold opening and the outlet manifold opening. The brazing frame includes a frame base and a frame wall extending from the frame base at an angle of at least 20 degrees from the base. The frame base includes an inner edge and the frame wall includes an outer edge. The inner edge surrounds and defines the area of the central flow region. The inner edge extends parallel to the outer edge along a perimeter of the first fluid passageway at a location adjacent the central flow region. The width of the central flow region at its widest point is the separation distance between the inner edge on one side of the frame and the inner edge on the other, opposite side of the frame. The first fluid passage is further defined between a first plate and a second plate brazed together at a perimeter of the first fluid passage by a brazing frame. The third plate is stacked on the second plate to define a second fluid passage between the second plate and the third plate.

The heat exchanger also includes a first inlet configured to receive a first fluid, a first outlet in fluid communication with the first inlet, a second inlet configured to receive a second fluid including a coolant, and a second outlet in fluid communication with the second inlet. The first fluid passage provides fluid communication of a first fluid between the first inlet and the first outlet. The second fluid passage provides fluid communication of a second fluid between the second inlet and the second outlet. Turbulators or fins may be located within the first fluid passage to increase heat transfer between the first fluid and the second fluid. A brazing frame is positioned between the first plate and the second plate. Other brazing filler materials, such as brazing paste made of iron or other materials, may also be used in the first fluid channel, in particular in the central flow area. A copper-based or iron-based braze filler material may be used in the second fluid channel.

In another embodiment, the heat exchanger comprises a brazing foil made of copper, and the brazing foil is located within the second fluid channel. The braze foil includes a sheet base extending around the second fluid channel and a sheet wall extending from the sheet base at an angle greater than 20 degrees. The sheet wall extends a first height from the sheet base. In the heat exchanger, the brazing foil is assembled between the second plate and the third plate. When the heat exchanger is assembled, the first edge at the outer periphery of the brazing foil is located between the second edge at the outer periphery of the second plate and the third edge at the outer periphery of the third plate. The brazing foil in the second channel is used as a brazing filler material for the braze joint between the first plate and the second plate and again for the braze joint between the second plate and the third plate, because when the heat exchanger is heated in a brazing furnace, the brazing foil melts and the brazing material from the brazing foil migrates to the joint between the first plate and the second plate. An iron-based brazing filler material may be used in the first fluid channel.

In another embodiment, the present invention provides a method of manufacturing a heat exchanger, the method comprising: providing a first inlet configured to receive a first fluid; providing a first outlet in fluid communication with the first inlet; providing a second inlet configured to receive a second fluid, the second fluid comprising a coolant; providing a second outlet in fluid communication with the second inlet; providing a first plate; the second plate is stacked on the first plate to define a first fluid channel between the first plate and the second plate, the first fluid channel providing fluid communication of the first fluid between the first inlet and the first outlet. The method further includes stacking a third plate on the second plate to define a second fluid passage between the second plate and the third plate, the second fluid passage providing fluid communication of a second fluid between a second inlet and a second outlet. The method further includes placing a copper foil frame between the first plate and the second plate such that the copper foil frame extends around a perimeter of the second plate, and brazing the first plate to the second plate, wherein the copper foil frame provides a filler metal to couple the first plate to the second plate. For this embodiment and method, the frame walls of the copper foil frame are bent at an angle relative to the frame base of the copper foil frame prior to punching the opening in the frame base. This element of the process provides rigidity to the frame for the stamping process.

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

Drawings

FIG. 1 is a perspective view of a heat exchanger according to one embodiment.

Fig. 2 is a cross-sectional view of the heat exchanger of fig. 1 taken along line 2-2 of fig. 1.

Fig. 3 is an enlarged view of a portion of fig. 2.

FIG. 4 is a cross-sectional view of the heat exchanger of FIG. 1 taken along line 4-4 of FIG. 1.

Fig. 5 is an enlarged view of a portion of fig. 4.

Fig. 6 shows the plates and copper foil frame of the heat exchanger of fig. 1.

Fig. 7 shows the copper foil frame of fig. 6.

FIG. 8 is a cross-sectional view of a heat exchanger according to another embodiment.

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.

Detailed Description

Fig. 1 shows a heat exchanger 10. In one embodiment, the heat exchanger 10 is an on-board oil cooler, more particularly a stratified core on-board oil cooler. The heat exchanger 10 includes a base plate 12 and a heat exchanger plate 14 stacked on the base plate 12. In one embodiment, the

plates

12, 14 are formed of stainless steel. The base plate 12 may be used to mount or couple the heat exchanger 10 to a vehicle. The substrate 12 includes a first inlet 16 and a first outlet 18, the first inlet 16 receiving a first fluid, and the first outlet 18 being in fluid communication with and downstream of the first inlet 16. In one embodiment, the first fluid comprises oil, and relatively warmer oil passes into the heat exchanger 10 through the inlet 16, and relatively cooler oil exits the heat exchanger 10 via the outlet 18. The substrate 12 also includes a second inlet 20 and a second outlet 22, the second inlet 20 receiving a second fluid, and the second outlet 22 being in fluid communication with and downstream of the second inlet 20. In one embodiment, the second fluid comprises a coolant for cooling the oil using the heat exchanger 10, as the first and second fluids are in thermal contact via thermal conduction through the plates 14 arranged between the first and second fluids. In an alternative configuration (not shown), the first inlet 16 is disposed on the opposite long side from the first outlet 18, and the second inlet 20 or the second outlet 22 is disposed on the same long side as the first inlet 16. In another alternative embodiment, not shown, the first inlet 16 is on the same narrow side as the second inlet 20.

Referring to fig. 2 and 3, the heat exchanger plates 14 comprise first plates 26 and second plates 28, which alternate in the stack of heat exchanger plates 14. The first plate 26 includes a base 30 and a dome 32 extending from the base 30. The domes 32 each include a hole 34 extending through the dome 32. The bore 34 aligned with the second inlet or coolant inlet 20 forms a coolant inlet manifold 36 of the heat exchanger 10. The bore 34 aligned with the second outlet or coolant outlet 22 forms a coolant outlet manifold 38 of the heat exchanger 10. The first panel 26 also includes an outer wall or edge 40 extending from the base 30 around the perimeter of the first panel 26.

The second plate 28 includes a base 42 and an aperture 44 extending through the base 42. The holes 44 aligned with the coolant inlet 20 form the coolant inlet manifold 36 of the heat exchanger 10. The holes 44 aligned with the coolant outlets 22 form the coolant outlet manifold 38 of the heat exchanger 10. The second panel 28 also includes an outer wall or edge 46 extending from the base 42 around the perimeter of the second panel 28. The edge 46 of the second plate 28 is received within the edge 40 of the first plate 26 to stack or nest the

plates

26, 28.

A first fluid channel 50 is formed between the first plate 26 and the second plate 28. The first fluid passage 50 provides fluid communication of a first fluid (e.g., oil) between the first inlet 16 and the first outlet 18. Referring to fig. 4 and 5, the holes 52 in the first plate 26 aligned with the inlet 16 form an oil inlet manifold 54, and the holes 52 aligned with the outlet 18 form an oil outlet manifold 56 of the heat exchanger 10. An oil inlet manifold 54 distributes oil to the first fluid passages 50, and an oil outlet manifold 56 collects oil from the passages 50 before directing the oil to the outlet 18.

In the illustrated embodiment, turbulators or fins 58 are located in the first fluid passage 50. Turbulators 58 provide turbulence to the flow in passage 50 to increase heat transfer between the oil and the coolant. In one method of manufacture, a brazing paste is partially applied to the turbulators 58 in specific locations to braze the turbulators 58 to the

plates

26, 28.

Referring to fig. 3, a third plate, which is another first plate 26, is stacked on the second plate 28 to define a second fluid or coolant fluid passage 60 between the

plates

26, 28. The coolant fluid passage 60 provides fluid communication of a second fluid or coolant between the inlet 20 and the outlet 22. The coolant flows through the inlet 20 and into the coolant inlet manifold 36 where it is distributed to the fluid channels 60. The coolant in the fluid passage 60 is used to cool the oil in the fluid passage 50 via heat transfer across the

plates

26, 28. The coolant is received from the channels 60 into the coolant outlet manifold 38, and the coolant exits the heat exchanger 10 through the coolant outlet 22.

Referring to fig. 3, 6 and 7, during manufacture, a copper foil frame 64 is placed between each of the first and

second plates

26, 28. When the heat exchanger is placed in a brazing furnace, the copper foil frame 64 melts, providing a filler metal for brazing and securing the first plate 26 to the second plate 28. The copper foil frame 64 extends only around the perimeter 66 of the plate (shown on the second plate 28 in fig. 6). That is, the copper material of the frame 64 does not extend into the interior region 68 of the panel 28. The copper foil frame 64 includes only a narrow strip of copper foil 70 that extends around the perimeter 66 of the plate 28. In addition, the narrow strips 70 extend around the holes 44 of the plates 28 that form the coolant manifolds 36, 38 so that the copper foil frame 64 is between the domes 32 of the first plate 26 and the base 42 of the second plate 28. This provides a filler metal for brazing the dome 32 to the second plate 28. A copper foil frame 64 is used in the first fluid or oil fluid passage 50 to braze the

plates

26, 28. The configuration of the frame 64 minimizes the amount of copper required as a filler metal to braze the

plates

26, 28 together within the oil gallery 60. Fluids such as oil can decompose copper over time and due to the use of the heat exchanger 10 and the contact between the copper and the oil. Therefore, it is desirable to minimize the amount of copper used in the oil fluid passage 50. The copper foil frame 64 includes a narrow strip of copper foil 70 that extends only around the perimeter 66 of the plate 28, which minimizes the amount of copper used in the oil gallery 50 while still providing sufficient filler metal for brazing.

As shown in fig. 6 and 7, the first fluid channel of the heat exchanger includes a central flow area 88, the central flow area 88 being within the perimeter of the first fluid channel and located between the inlet and outlet manifold openings. Brazing frame 64 includes a frame base 84 and a frame wall 86, with frame wall 86 extending from frame base 84 at an angle of at least 20 degrees from base 84. The frame base 84 includes an inner edge 85 and the frame wall includes an outer edge 87. The inner edge 85 surrounds and defines the area of the central flow region 88. The inner edge 85 extends parallel to the outer edge 87 along the perimeter of the first fluid passage at positions W1, W2, L1, L2 adjacent the central flow region 88. The width 92 of the central flow area 88 at the widest point of the central flow area 88 is the separation distance between the inner edge 85 on one long side L1 of the frame and the inner edge 85 on the other opposite long side L2 of the frame. The length 90 of the central flow region 88 at the longest point of the central flow region 88 is the separation distance between the inner edge 85 on one broad side W1 of the frame and the inner edge 85 on the other opposite broad side W2 of the frame. The width dimension of the frame wall 86 is greater than or equal to the width dimension of the frame base 84 when measured at a point along one of the sides of the copper foil frame, the measurement being taken along a cross-section of the one of the sides of the frame at the point.

Fig. 8 shows an alternative embodiment of the heat exchanger according to the invention as shown in the previous fig. 3, 6 and 7, wherein, as shown in fig. 8, the braze joint between the first plate 126a and the second plate 128 is made of a brazing foil 164, which is at least partly made of copper, and which is arranged between the second plate 128 and the third plate 126 b. Fig. 8 shows similar elements to fig. 3. As shown above in fig. 3, the second plate 128 and the third plate 126b form a second fluid passage 160 therebetween. Thus, in this embodiment, copper-based filler material in the form of braze foil 164 is located in the coolant channels. In the embodiment of fig. 8, the brazing foil 164 has an outer edge 166 that extends beyond an outer edge 174 of the second plate, covering at least the contact area between the second plate 128 and the third plate 126 b. The outer edge 166 may be located between the outer edge 174 and the outer edge 176 of the third plate, or may be located at the outer edge 176 of the third plate. During a brazing operation for the heat exchanger, the material of the brazing sheet 164 melts to create a first braze joint 168a between the second plate 128 and the third plate 126 b. Additionally, the material of the braze sheet 164 migrates to the exterior of the heat exchanger to create a second braze joint 168b between the second plate 128 and the first plate 126 a. Thus, this embodiment further inhibits copper from the brazing filler material from entering the first fluid channel and mixing with the first fluid, which may be oil.

In another embodiment of fig. 1 to 7, the heat exchanger 10 is manufactured by: forming a first plate 26 and a second plate 28 having upturned side walls, forming a brazing frame by bending the frame walls at an angle from the frame base, and then stamping an opening into the frame base after bending the frame walls. After forming the first and

second plates

26, 28 and the brazing frame 64. The first and

second plates

26, 28 are stacked by alternating the first and

second plates

26, 28 and stacking a brazing frame between the first and

second plates

26, 28. Bending the brazing frame 64 prior to stamping provides additional rigidity to the brazing frame 64, thereby improving the stamping and assembly operations.

Various features and advantages of the invention are set forth in the following claims.

Claims

1. A heat exchanger, comprising:

a first inlet configured to receive a first fluid;

a first outlet in fluid communication with the first inlet;

a second inlet configured to receive a second fluid, the second fluid comprising a coolant;

a second outlet in fluid communication with the second inlet;

a first plate;

a second plate stacked on the first plate to define a first fluid channel between the first plate and the second plate, the first fluid channel providing fluid communication of the first fluid between the first inlet and the first outlet;

a third plate stacked on the second plate to define a second fluid passage between the second plate and the third plate, the second fluid passage providing fluid communication of the second fluid between the second inlet and the second outlet; and

a copper foil frame positioned between the first plate and the second plate, the copper foil frame configured to provide a filler metal for brazing the first plate to the second plate, wherein the copper foil frame extends around a perimeter of the second plate.

2. The heat exchanger of claim 1, wherein the first plate comprises a base and a dome extending from the base, wherein the dome comprises a hole extending through the dome, the hole being in fluid communication with the second inlet and providing a flow path for the second fluid, and wherein the copper foil frame is located between the dome of the first plate and the second plate to provide a filler metal to braze the dome of the first plate to the second plate.

3. The heat exchanger of claim 1, wherein the copper foil frame extends beyond an outer edge of the second plate and beyond an interface between the second plate and the third plate.

4. The heat exchanger of claim 1, further comprising a turbulator and a braze paste, the turbulator being located in the first fluid channel, and the braze paste being located between the turbulator and at least one of the first plate and the second plate for brazing the turbulator to the at least one of the first plate and the second plate.

5. The heat exchanger of claim 1, wherein the copper foil frame comprises a frame base having an inner edge and a frame wall having an outer edge, wherein the inner edge surrounds and defines an area of a central flow region, and wherein the inner edge extends parallel to the outer edge at least partially around the central flow region.

6. The heat exchanger of claim 1, wherein the copper foil frame comprises a frame base and a frame wall, and wherein the frame wall extends away from the frame base at an angle greater than 20 degrees.

7. The heat exchanger of claim 1, wherein the copper foil frame comprises a frame base and a frame wall, and wherein a width dimension of the frame wall is greater than or equal to a width dimension of the frame base when measured along a cross-section of one side of the copper foil frame.