JPH0645165Y2 - Oil cooler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of an oil cooler having a structure in which a plurality of plate tubes are stacked in a predetermined number of stages via joint rings.

[Conventional technology]

Conventionally, as this type of oil cooler, as shown in FIG. 4, a plurality of plate tubes 1 are connected to a joint ring 2.
In some cases, the element 3 is formed by stacking a predetermined number of the elements through the, and the element 3 is housed in a case 4 formed of aluminum or the like and attached to an engine (not shown) for use.

In the plate tube 1, the rectangular tray 5 and the plate 6 are overlapped and the outer periphery thereof is welded, and the inner fins 8 are arranged in parallel in the internal space 7 formed by the tray 5 and the plate 6. The plate tube 1 has a structure in which a plurality of flow passages 9 are formed, and the plate tube 1 has through holes 10a, 10b vertically penetrating near the ends in the longitudinal direction thereof.
Are formed.

For assembly, the upper and lower plate tubes 1,1
The joint ring 2 at the positions of the through holes 10a, 10b between
When a predetermined number of plate tubes 1 are stacked and fixed while sandwiching between them, each of the through holes 10a and 10b of the plate tube 1 at the uppermost position has a flange having circular holes serving as an inlet and an outlet of oil to be cooled. 11a and 11b are fixed respectively, and the through holes 10a and 10b of the lowermost plate tube 1 are closed by the lower plate 12. Therefore, the plate tubes 1, 1 are in communication with each other through the joint ring 2, and a flow passage 13 for a cooling medium such as cooling water or cooling air is formed between the upper and lower plate tubes 1, 1.

Then, the oil warmed by the engine is injected from the inlet flange 11a, distributed into each plate tube 1 through the joint ring 2, flows through the flow passage 9 in the plate tube 1, and is discharged from the outlet flange 11b. To be done. On the other hand, a cooling medium such as cooling water or cooling air cools the oil by flowing through the flow passage 13 between the plate tubes 1 and 1 in the direction opposite to or parallel to the oil flow.

However, in the conventional oil cooler as described above,
In general, the joint ring 2 has a cylindrical outer shape, and therefore, as shown in FIG. 5, when cooling water hits the joint ring 2, flow separation occurs, and in the rear basin A of the joint ring 2, A site B (hereinafter referred to as dead water area B) where cooling water hardly enters occurs.

As a result of the experiment, this dead water area B is equivalent to an area of about 2.5 times the outer diameter cross-sectional area of the joint ring 2. Due to the appearance of this dead water area B, the heat dissipation area of the oil cooler decreases. , It was found that the heat dissipation performance deteriorates. That is, the larger the outer diameter of the joint ring 2 is, the more the dead water region B having a cross-sectional area twice or more thereof appears.
Although it was found that this reduces the heat dissipation performance, for example, when the outer diameter of the joint ring 2 was increased from 31 mm to 44 mm, the heat dissipation of the oil cooler decreased by 10%.

From the above experimental data, in order to prevent the heat dissipation performance of the oil cooler from being deteriorated, it is possible to solve it by making the outer diameter of the joint ring 2 as small as possible. Absent. As a result, the amount of oil flow is also limited to the set value or less, which causes various problems that it cannot be put to practical use.

In order to eliminate the above-mentioned conventional drawbacks
Japanese Patent Publication No. 84 discloses an element of a heat exchanger in which a guide plate bent in a dogleg shape is erected at a slight distance from the outer circumference of the joint ring.

Thus, in this invention, the cooling medium is guided by the inner surface of the bent portion of the guide plate and flows along the outer periphery of the joint ring, so that there is no dead water region in the rear basin of the joint ring. Play.

[Problems to be solved by the invention]

However, in the device disclosed in Japanese Utility Model Laid-Open No. 63-159684, by forming the bent portion on the guide plate, there is a remarkable effect that no dead water region occurs in the rear basin of the joint ring, but this folding There is a problem that a new dead water area occurs in the rear basin of the outer side of the bend.

[Means for solving problems]

The present invention was made to solve the problems of the above-mentioned Japanese Utility Model Laid-Open No. 63-159684.
The purpose of the present invention is to provide a product that can reduce the dead water area generated by the joint ring as much as possible and improve the heat dissipation performance, and the gist thereof is a plurality of plate tubes in which oil flows inside. When a predetermined number are stacked by connecting them in a communicating state with a joint ring, the flow direction of the cooling medium from the vicinity of the outer periphery of the joint ring to the downstream region of the joint ring of the cooling medium flowing between the plate tubes. The oil cooler is characterized in that a plurality of cylindrical projections are arranged in a staggered pattern.

〔Example〕

1 is a perspective view of the present invention with a part of the oil cooler removed, a cross-sectional view of the essential parts of the oil cooler shown in FIG. 2, and an explanatory view of the operation of the oil cooler shown in FIG. As will be described in more detail below, among the elements in FIGS. 1 to 3, the same elements as those in FIGS. 4 and 5 described above are denoted by the same reference numerals, and Since the structure of the element is almost the same as the structure of the conventional water-cooled oil cooler described above, the detailed description thereof will be omitted and only the gist of the present invention will be described in detail.

In the figure, 13 is a flow passage for a cooling medium such as a cooling liquid or cooling air formed between the upper and lower plate tubes 1, 1.
In the flow passage 13, a plurality of columnar protrusions 14 (14-1 to 14-3) are erected at appropriate positions in a portion corresponding to the downstream region A of the joint ring 2 with respect to the flow direction of the cooling medium. There is. Here, when an example of the specific arrangement and dimensions of the cylindrical protrusion 14 is shown below, as shown in FIG.
When the distance between the pair of upper and lower protrusions 14, 14 is X and the distance from the center of the joint ring 2 to the cylindrical protrusion 14 is 1, It is what It should be noted that these numerical values are the optimum ones obtained by trial and error while observing the flow of the cooling water in the experimental apparatus using the outer diameter D of each cylindrical projection 14 of 10 mm.

Next, the operation of the oil cooler according to the present invention will be described in detail.
It enters into the through hole 10a from 11a, is distributed to each plate tube 1 by the joint ring 2, flows through the flow passage 9 in this plate tube 1, and passes through the through hole 10b of the flange 11b at the outlet.
Emitted from. On the other hand, the cooling medium such as cooling water flows through the flow passage 13 between the plate tubes 1 and 1 in the direction opposite to the oil flow, that is, from the outlet flange 11b side to the inlet flange 11a side, or the oil flow. The oil is cooled by flowing in the direction parallel to.

Here, when the cooling medium flows through the flow passage 13, as shown in FIG. 3, the cooling medium collides with the outer peripheral surface of the joint ring 2 to cause flow separation as described in the cooling medium. In the downstream region A of the joint ring 2, a first columnar projection 14-1 on which the cooling medium first collides is provided in the vicinity of the outer periphery of the joint ring 2. As a result, the cooling medium first hits the first cylindrical protrusions 14-1 and 14-1 protruding near the outer periphery, and the joint ring 2
Since it is changed in the direction along the outer circumference on the downstream side of, the separation of the cooling medium by the joint ring 2 does not occur.

Then, behind the first cylindrical protrusion 14-1, that is, along the flow direction of the cooling medium, the second cylindrical protrusion 14-2 and the third cylindrical protrusion 14-3 are staggered, respectively. Since it is projected like a circle, the first cylindrical protrusion 14-1
The cooling medium flowing without hitting or hitting against the second stylus-like second cylindrical projection 14-2
And the third cylindrical protrusion 14-3, and the joint ring 2 is changed in the direction of the wake region A. Therefore, the area of the dead water region (separation flow) B generated in the wake region A of the joint ring 2 is suppressed to half or less of that in the case of a normal oil cooler, even if the following phenomenon is taken into consideration.

That is, in the present invention, the dead water area (the water area shaded with diagonal lines) C as shown in FIG.
However, since the outer shape of each of these projections 14 is cylindrical, the area of the dead water area C generated by this cylindrical projection 14 is extremely small, and the dead water area B and each of the cylindrical projections are
Even if the dead water area C by 14 is summed up, it can be suppressed to less than half that of the conventional oil cooler.

[Effect of device]

In the oil cooler according to the present invention, as described above, when a plurality of plate tubes in which oil flows inside are connected by a joint ring in a communicating state and stacked for a predetermined number of stages, the oil flows between the plate tubes. In the downstream region of the joint ring of the cooling medium, a plurality of columnar protrusions are arranged in a staggered manner from the vicinity of the outer periphery of the joint ring in a staggered manner. Since the area of is greatly reduced and the heat dissipation efficiency of the cooler is further improved, there is an effect that the desired heat dissipation effect can be achieved with the joint ring having the same outer diameter as the conventional one.

[Brief description of drawings]

FIG. 1 is a perspective view in which a part of the oil cooler according to the present invention is cut away, FIG. 2 is a lateral cross-sectional view of the essential parts of the oil cooler, FIG. 3 is an explanatory view of the operation of the oil cooler, and FIG. FIG. 5 is a perspective view in which a part of the water-cooled oil cooler is cut away, and FIG. 5 is an operation explanatory view of the oil cooler. 1 ... Plate tube, 2 ... Joint ring, 3
…… Element, 4 …… Case, 7 …… Internal space, 8 ・ ・ ・
… Inner fins, 9, 13 …… Flow passages, 10a, 10b …… Through holes, 11a, 11b …… Flange, 12 …… Lower plate, 14
…… Cylindrical projections, A …… Wake areas, B, C …… Dead water areas.

Claims (1)

[Scope of utility model registration request] 1. A plurality of plate tubes in which oil flows inside are connected by a joint ring so as to be in communication with each other, and a predetermined number of layers are stacked so that the cooling medium flowing between the plate tubes is connected to the joint ring. In the downstream area,
An oil cooler in which a plurality of cylindrical projections are arranged in a staggered manner from the vicinity of the outer periphery of the joint ring in the flow direction of the cooling medium.