Radiator

Abstract

To reduce thermal stress generated in flat tubes to improve durability and to improve the performance of a radiator by uniformizing a flow rate in each flat tube.SOLUTION: Provided is a radiator including: an inlet pipe connected to one side surface 11 in a depth direction of an inlet tank; and an outlet pipe connected to one side surface 11 in the depth direction in an outlet tank 8 on the same side surface side as the inlet pipe. The outlet pipe has an extension part 15 that extends from the one side surface 11 of the outlet tank 8 toward the other side 14 opposite the one side surface 11 of the outlet tank 8 inside the outlet tank 8. The extension part 15 is located at a position overlapping with an imaginary extension part of the flat tube 2 that is closest to one side surface 11 of the flat tubes 2, and within a range excluding a position overlapping with an imaginary extension part of the flat tube 2 closest to the other side surface 14.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a radiator. [Background technology]

[0002] A radiator (heat exchanger) is provided in a cooling circuit to cool engines of construction machines, industrial machines, etc. A conventional radiator includes a core in which flat tubes are arranged in a plurality of rows in the width direction, and an inlet tank and an outlet tank arranged at both ends of the core so that both ends of the flat tubes are connected, and an inlet pipe that flows cooling water in the cooling circuit into the inside of the radiator is connected to one side of the inlet tank in the row direction of the flat tubes, and an outlet pipe that flows cooling water out of the radiator is connected to one side of the outlet tank in the row direction of the flat tubes on the same side as the inlet pipe.

[0003] Generally, a thermostat is provided in the cooling circuit to control the flow of cooling water from the engine to the radiator. However, when the engine is started in a low-temperature environment, the thermostat repeatedly opens and closes in a short period of time, and every time the thermostat opens, the cooling water warmed by the engine flows into the low-temperature radiator, causing thermal stress in the flat tubes.

[0004] Therefore, in order to improve durability against this thermal stress, a technique has been proposed in which a reinforcing member is provided in the flat tube (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-45134 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the above-mentioned type of radiator in which the inlet pipe and the outlet pipe are arranged on one side of the row direction of the flat tubes in the inlet tank and the outlet tank, the distance from the opening of the flat tube to the opening of the inlet pipe or the outlet pipe varies depending on the row of the flat tubes, so the flow rate of the cooling water flowing through the flat tubes varies depending on the position of the row of the flat tubes, and the flow rate of the cooling water is particularly high in the flat tubes arranged in the vicinity of the inlet pipe or the outlet pipe, resulting in a large difference in the flow rate of the cooling water between the flat tubes.

[0007] When the difference in flow rate between the flat tubes becomes large, there are problems such as a decrease in the heat exchange performance of the radiator and an increase in thermal stress generated in the flat tubes. However, it is difficult for the technology described in Patent Document 1 to solve all of these problems, and there is a risk of causing problems in the performance and durability of the radiator.

[0008] The present invention has been made to solve the above-mentioned problems, and has an object to provide a radiator that can reduce thermal stress generated in the flat tubes by making the flow rate in each flat tube uniform, thereby improving durability and performance. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention provides a radiator (1) including a core (5) in which flat tubes (2) are arranged in a plurality of rows in the depth direction, an inlet tank (7) and an outlet tank (8) arranged at both ends of the core (5) so that both ends of the flat tubes (2) are in communication with each other, an inlet pipe (10) connected to one side surface (9) in the depth direction of the inlet tank (7), and an outlet pipe (12) connected to one side surface (11) in the depth direction of the outlet tank (8) on the same side as the inlet pipe (10), (12) has an extension portion (15) extending from the one side surface (11) of the outlet tank (8) toward the other side surface (14) facing the one side surface (11) of the outlet tank (8) inside the outlet tank (8), and the extension portion (15) is located within a range that overlaps with a virtual extension portion of the flat tube (2) closest to the one side surface (11) of the flat tube (2) and excludes a position that overlaps with a virtual extension end portion of the flat tube (2) closest to the other side surface (14).

[0010] In the present invention, in a radiator (1) in which the flat tubes (2) are arranged in four or more rows in the depth direction in the core (5), it is preferable that the tip (15a) of the extension portion (15) is located within a range (L2) from the central position in the depth direction of the flat tube (2) that is closest to the one side surface (11) of the outlet tank (8) to the opening end on the other side surface (14) side of the flat tube (2) that is third closest to the one side surface (11) of the outlet tank (8).

[0011] In the present invention, in a radiator (1) in which the flat tubes (2) are arranged in three rows in the depth direction in the core (5), it is preferable that the tip (15a) of the extension portion (15) is located within a range (L2) from the central position in the depth direction of the flat tube (2) that is closest to the one side surface (11) of the outlet tank (8) to the opening end on the other side surface (14) side of the flat tube (2) that is second closest to the one side surface (11) of the outlet tank (8).

[0012] In the radiator (1) according to the present invention described above, it is preferable that the tip (15a) of the extension portion (15) is located within a range (L1) from a central position in the depth direction of the flat tube (2) that is closest to the one side surface (11) of the outlet tank (8) to a central position in the depth direction of the flat tube (2) that is second closest to the other side surface (14) of the outlet tank (8).

[0013] In the radiator (1) according to the present invention described above, it is preferable that an opening (16) is formed on the side of the extension portion (15) opposite to the flat tube (2). Effect of the Invention

[0014] According to the present invention, by making the flow rate in each flat tube uniform, it is possible to reduce the thermal stress generated in the flat tube, thereby improving durability, and also to improve the performance of the radiator, thereby achieving various other effects. [Brief description of the drawings]

[0015] [Figure 1] 1 is a front view showing a radiator according to an embodiment of the present invention; [Diagram 2] 1 is a side view showing a radiator according to an embodiment of the present invention. [Diagram 3] 2 is a cross-sectional view taken along line AA in FIG. 1. [Figure 4] 2 is a cross-sectional view showing an internal flow rate adjustment mechanism of the radiator according to the embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings, in which Fig. 1 is a front view showing a radiator according to an embodiment of the present invention, Fig. 2 is a side view showing a radiator according to an embodiment of the present invention, Fig. 3 is a cross-sectional view taken along line AA in Fig. 1, and Fig. 4 is a cross-sectional view showing an internal flow rate adjustment mechanism of the radiator according to an embodiment of the present invention.

[0017] In addition, Fr, Rr, L, R, U, and D shown in each drawing indicate front, rear, left, right, top, and bottom, respectively. Although terms indicating directions and positions are used in this specification, these terms are used for convenience of explanation and do not limit the technical scope of the present invention.

[0018] As shown in Figures 1 and 2, a radiator (heat exchanger) 1 according to an embodiment of the present invention has a core 5 including a plurality of flat tubes 2, a plurality of fins 3, and a pair of upper and lower header plates 4.

[0019] In the core 5, four tube rows 6A, 6B, 6C, 6D (see FIG. 4) are arranged in the depth direction, which is the front-rear direction, in which fins 3 are interposed between a large number of flat tubes 2 arranged in the left-right width direction. The flat tubes 2 are formed in a cylindrical shape having an elongated, approximately elliptical cross section in the front-rear direction. The flat tubes 2 and the fins 3 are arranged alternately in the left-right width direction in a posture extending in the up-down direction. Each header plate 4 is provided with a plurality of tube insertion holes (not shown), and the edges of each tube insertion hole are burred. Both upper and lower ends of each flat tube 2 are inserted into the tube insertion holes of the pair of header plates 4. Here, in this specification and claims, the "width direction" is defined as the left-right direction in FIG. 1, and the "depth direction" is defined as the front-rear direction in FIG. 2 to FIG. 4.

[0020] 1 and 2, an inlet tank 7 and an outlet tank 8 are provided at the upper and lower ends of the core 5 via header plates 4, and the tube rows 6A, 6B, 6C, and 6D (see FIG. 4) share the inlet tank 7 and the outlet tank 8. An inlet pipe 10 is connected to the inlet tank 7 on the left side of one side surface 9 in the depth direction (the rear side surface in the figure) when viewed from the front. The inlet pipe 10 has a cylindrical shape and protrudes forward from one side surface 9 of the inlet tank 7.

[0021] 1 and 2, as well as Fig. 3 and 4, an outlet pipe 12 is connected to the right side of one side surface 11 in the depth direction (the rear side surface in the figures) when viewed from the front of the outlet tank 8. The outlet pipe 12 has a cylindrical outer portion 13 that protrudes forward from one side surface 11 of the outlet tank 8, and an extension portion 15 that extends from the outer portion 13 inside the outlet tank 8 toward the other side surface 14 (the front side surface in the figures) that faces the one side surface 11 of the outlet tank 8, and this extension portion 15 acts as an internal flow rate adjustment mechanism having a baffle function.

[0022] 4, the extension 15 of the outlet pipe 12 is preferably formed so that its tip 15a is located within a range L1 from the center position in the depth direction of the flat tube 2 of the tube row 6A closest to one side surface 11 (rear side surface in the drawing) of the outlet tank 8 to the center position in the depth direction of the flat tube 2 of the tube row 6C second closest to the other side surface 14 (front side surface in the drawing). This makes it possible to prevent the flow rate from concentrating in the flat tubes 2 closest to the other side surface 14, while suppressing an increase in the flow rate of the cooling water in the flat tubes 2 arranged in the vicinity of the outlet pipe 12, thereby suppressing an increase in the difference in the flow rate of the cooling water between the flat tubes 2.

[0023] It is preferable that an opening 16 is formed in a lower portion of the extension 15 on the side opposite to the flat tube 2, the opening 16 being cut out in a semicircular shape when viewed from the tip 15a side of the extension 15 (rear side in Figs. 3 and 4). Although not shown, the opening 16 may be cut out in a fan shape when viewed from the tip 15a side, or may be formed by a plurality of through holes instead of a cutout. The extension 15 may have a cylindrical shape without forming the opening 16 on its lower side.

[0024] 1 and 2, in the radiator 1 having the above-mentioned configuration, high-temperature cooling water warmed by the engine flows from an inlet pipe 10 through an inlet tank 7 into each of the flat tubes 2 of each of the tube rows 6A, 6B, 6C, and 6D (see FIG. 4) by the drive of a circulation pump (not shown) installed in the cooling circuit. Cooling air is circulated in the front-rear direction on the outer surface side of the flat tubes 2 by a fan (not shown), and heat exchange occurs between the cooling air and the cooling water in the flat tubes 2. Thereafter, the cooling water cooled by this heat exchange flows through an outlet tank 8 and flows out from an outlet pipe 12, and circulates back to the engine.

[0025] When the cooling water flows through the flat tubes 2 of the core 5 of the radiator 1 in this manner, the flat tubes 2 of the first to third tube rows 6A to 6C (see FIG. 4) counting from the side surface 11 to which the outlet pipe 12 is connected and the flat tubes 2 on the outlet pipe 12 side are arranged to overlap the extension portion 15 in a plan view, so that the flow resistance of the cooling water flowing from these flat tubes 2 into the outlet tank 8 becomes large. This makes it possible to change the flow of the cooling water so as to avoid the flow rate of the cooling water concentrating on these flat tubes 2 arranged in the vicinity of the outlet pipe 12, and therefore to equalize the flow rate of the cooling water in each flat tube 2. This makes it possible to reduce the thermal stress generated in the flat tubes 2 in the vicinity of the outlet pipe 12, and to improve the performance and durability of the radiator 1.

[0026] Furthermore, in a cooling circuit in which the circulation pump is disposed upstream of the radiator 1, the cooling water that flows from the flat tubes 2 into the vicinity of the outlet pipe 12 in the outlet tank 8 is pressed against the extension 15, increasing the flow resistance of the cooling water, thereby further enhancing the above-mentioned effects of the present invention. In this case, by narrowing the gap between the lower ends of the flat tubes 2 and the upper end of the extension 15 of the outlet pipe 12, the above-mentioned effects of the present invention can be further enhanced.

[0027] Furthermore, in a cooling circuit in which the circulation pump is disposed downstream of the radiator 1, the cooling water that flows from the flat tubes 2 into the vicinity of the outlet pipe 12 of the outlet tank 8 is pulled around the extension 15 and drawn into the outlet pipe 12. Therefore, it is not easily affected by the size of the gap between the lower end of the flat tubes 2 and the upper end of the extension 15 of the outlet pipe 12, and therefore the design freedom of the protrusion of the flat tubes 2 into the outlet tank 8 and the positioning of the extension 15 of the outlet pipe 12 can be improved.

[0028] 4, the tip 15a of the extension 15 of the outlet pipe 12 may be formed to be located within a range L2 from the center position in the depth direction of the flat tube 2 closest to one side surface 11 of the outlet tank 8 to the open end on the other side surface 14 side of the flat tube 2 that is third closest to the one side surface 11 of the outlet tank. This suppresses the flow rate in one to three of the flat tubes 2 closest to the one side surface 11 and equalizes the flow rate in each flat tube 2, thereby reducing the thermal stress generated in the flat tubes 2 and improving durability as well as improving the performance of the radiator.

[0029] Furthermore, the extension portion 15 of the outlet pipe 12 may be formed so as to be located within a range that overlaps with the imaginary extension portion of the flat tube 2 of the tube row 6A that is closest to one side surface 11 of the flat tubes 2, excluding the position that overlaps with the imaginary extension portion of the flat tube 2 of the tube row 6D that is closest to the other side surface 14.

[0030] In the above description of the embodiment of the present invention, a radiator 1 having four tube rows 6A, 6B, 6C, 6D arranged therein has been described. However, the application of the present invention is not limited to such a radiator 1, and the present invention can also be applied to, for example, a radiator having three tube rows arranged therein, or a radiator having five or more tube rows arranged therein.

[0031] For example, in a radiator having three tube rows, the tip 15a of the extension 15 of the outlet pipe 12 is preferably formed to be located within a range L2 from the center position of the flat tube 2 of the tube row closest to one side surface 11 of the outlet tank 8 to the open end on the other side surface 14 side of the flat tube 2 of the tube row second closest to one side surface 11 of the outlet tank 8. In this case as well, the same effect as described above can be obtained.

[0032] Also, for example, in a radiator having five or more tube rows, it is preferable that the tip 15a of the extension 15 of the outlet pipe 12 is formed so as to be located within the range L2 from the center position of the flat tube 2 of the tube row closest to one side surface 11 of the outlet tank 8 to the open end on the other side surface 14 side of the flat tube 2 of the tube row third closest to the one side surface 11. In this case as well, the same effect as described above can be obtained.

[0033] The above description of the embodiment of the present invention shows one aspect of the internal flow rate adjustment mechanism of the radiator according to the present invention, and the technical scope of the present invention is not limited to the above embodiment. The present invention may be modified, substituted, or altered in various ways without departing from the spirit of the technical idea, and the claims include all embodiments that may be included within the scope of the technical idea. [Explanation of symbols]

[0034] 1 Radiator 2 Flat tube 5 cores 7 Inlet tank 8. Outlet Tank 9 (One side of the inlet tank) 10 Inlet pipe 11 (Outlet tank) One side 12. Outlet pipe 14 (Outlet tank) other side 15 Extension part (internal flow rate adjustment mechanism) 15a Tip 16 Opening L1: The distance from the center position in the depth direction of the flat tube closest to one side of the outlet tank to the center position in the depth direction of the second closest flat tube from the other side of the outlet tank L2: The range from the center position in the depth direction of the flat tube closest to one side of the outlet tank to the open end of the other side of the flat tube that is third closest to one side of the outlet tank

Claims

1. A radiator (1) comprising: a core (5) in which flat tubes (2) are arranged in a plurality of rows in the depth direction; an inlet tank (7) and an outlet tank (8) arranged at both ends of the core (5) so that both ends of the flat tubes (2) are in communication with each other; an inlet pipe (10) connected to one side surface (9) in the depth direction of the inlet tank (7); and an outlet pipe (12) connected to one side surface (11) in the depth direction of the outlet tank (8) on the same side as the inlet pipe (10), The outlet pipe (12) has an extension (15) extending from the one side surface (11) of the outlet tank (8) toward the other side surface (14) facing the one side surface (11) of the outlet tank (8) inside the outlet tank (8), and the extension (15) is located at a position overlapping with an imaginary extension portion of the flat tube (2) closest to the one side surface (11) of the flat tube (2) and within a range excluding a position overlapping with an imaginary extension portion of the flat tube (2) closest to the other side surface (14).

2. 2. The radiator according to claim 1, wherein in the radiator (1) in which the flat tubes (2) are arranged in four or more rows in the depth direction in the core (5), the tip (15a) of the extension portion (15) is located within a range (L2) from a central position in the depth direction of the flat tube (2) closest to the one side surface (11) of the outlet tank (8) to an opening end on the other side surface (14) of the flat tube (2) that is third closest to the one side surface (11) of the outlet tank (8).

3. 2. The radiator according to claim 1, wherein in a radiator in which the flat tubes (2) are arranged in three rows in the depth direction in the core (5), the tip (15a) of the extension portion (15) is located within a range (L2) from a central position in the depth direction of the flat tube (2) that is closest to the one side surface (11) of the outlet tank (8) to an opening end on the other side surface (14) of the flat tube (2) that is second closest to the one side surface (11) of the outlet tank (8).

4. The radiator (1) according to claim 1, characterized in that the tip (15a) of the extension portion (15) is located within a range (L1) from a center position in the depth direction of the flat tube (2) that is closest to the one side surface (11) of the outlet tank (8) to a center position in the depth direction of the flat tube (2) that is second closest to the other side surface (14) of the outlet tank (8).

5. The radiator (1) according to any one of claims 1 to 4, wherein an opening (16) is formed on the extension portion (15) on a side opposite to the flat tube (2).

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