JP2000283666A - Egr cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a tube against damage even if air is left at the corner of a tube sheet after deaeration by fixing a plurality of baffle plates between the tube sheets, forming each baffle plate into semicircular shape inscribing a tubular body and making a large number of holes for inserting tubes in each baffle plate. SOLUTION: EGR exhaust gas flows into an EGR cooler through an EGR circuit coupled with a connecting metal 3. Cooling water flows from a cooling water circuit into the body 1 and passes through the body smoothly while being guided to snake by means of a plurality of baffle plates 5 before flowing into the cooling water circuit. A cut 7 in the baffle plate 5 serves as an air passage when it is located at an upper part and since the air 17 being left at the corner of a deaeration opening 14 is located at a highest position when the baffle plate 5 is fixed while inclining upward toward the deaeration opening 14, a tube 2 is located in cooling water W and protected against damage. The tube 2 can be protected against damage due to the air 17 so long as the tube 2 is not connected to the upper region of a tube sheet 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting member for connecting a gas circuit to both ends of a tubular body, the tubes being fixed to a tube sheet having a large number of holes provided at both ends of the tubular body. The present invention relates to an EGR cooler device provided with a connection port connected to a cooling water circuit on an outer periphery.

[0002]

2. Description of the Related Art A water-cooled multi-tube cooler used for an EGR cooler or the like is known.

[0003] However, in the above-mentioned technology, the cooler device requires exhaust gas condensed water generated by cooling in a tube serving as an exhaust gas passage.

On the other hand, an air vent hole is provided in the vicinity of a tube sheet of a cooler device for bleeding air in the cooling water. Burring is applied to the holes, so that a certain distance is required between the tube sheet and the air holes or water holes for processing. For this reason, due to the inclination of the cooler device, an air reservoir having a triangular cross-sectional shape is formed at the corner, and the exhaust gas temperature at the cooler inlet is considerably high. Can be

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems of the prior art, and there is no breakage of the tube even if air which is not exhausted by bleeding air is present at the corner of the tube sheet. It is intended to provide an EGR cooler device.

[0006]

According to the present invention, tubes are fixed to a tube sheet having a large number of holes provided at both ends of a cylindrical body, and gas circuits are connected to both ends of the cylindrical body. In the EGR cooler device provided with a connecting metal fitting and a connecting port connected to a cooling water circuit on an outer periphery, a plurality of partition plates are attached between the tube sheets, and the partition plates are provided inside the tubular body. It is formed in a semicircular shape in contact with the tube, and has a number of holes into which the tube is inserted.

Further, according to the present invention, it is preferable that the plurality of partition plates are alternately arranged up and down such that straight portions face each other between the tube sheets.

Further, according to the present invention, it is preferable that a notch is provided in a part of a semicircle of the partition plate.

According to the present invention, the tubes are fixed to the tube sheet having a large number of holes provided at both ends of the tubular body, and connection fittings for connecting a gas circuit are provided at both ends of the tubular body. In the EGR cooler device provided with a connection port for connecting to the cooling water circuit, a region where no tube is attached exists above the tube sheet. When the tube comes into contact with the air accumulated inside the EGR cooler main body, the tube is considered to be damaged. Here, the tubes that may come into contact with the air are only the tubes attached to the upper part of the tube sheet. Therefore, if the tube is not provided on the upper portion of the tube sheet, the breakage of the tube due to the contact with the air accumulated inside the main body is prevented.

In addition to the above, according to the present invention, the air vent is disposed at a vertically upper portion of the EGR cooler main body,
There is no problem even if the inlet / outlet of the cooling water is provided at a position inclined with respect to the vertical direction with respect to the air vent.

[0011]

FIG. 1 is a partial sectional side view of an EGR device according to the present invention. A tube sheet 15 (see FIG. 3) is fixed to both ends of a main body 1 formed in a cylindrical shape. A plurality of tubes 2 are fixed to the tube sheet 15.

At both ends of the main body 1, connection fittings 3, 3 having a flange 4 connected to an EGR circuit are attached. A connection port 12 for a cooling water outlet is provided at an upper portion at the end, and an air vent 14
Is attached.

Referring to FIG. 2, inside the main body 1, a hole 2a formed in a semicircular shape and through which the tube 2 penetrates is formed.
And a partition plate 5 having a notch 7 parallel to the straight portion 5a.
However, the cooling water inlet side is at the lower part, and the outlet side is at the upper part in the
Are mounted alternately so as to face each other.

The upper space 6 formed between the notch 7 of the partition plate 5 and the inside of the main body 1 forms a passage for air accumulated in the upper part of the main body, and the lower space 8 eliminates stagnation of cooling water. It becomes a passage.

Although the present embodiment shows an example in which the number of the partition plates is two, the present invention is not limited to this. If the cooling water flow is arranged to cool the tubes 2 evenly depending on the length of the cooler, the present invention is not limited thereto. Good.

The operation will be described below with reference to FIGS. Exhaust gas, which is EGR, flows into the EGR cooler via an EGR circuit (not shown) connected to the connection fitting 3 on the right side in the figure. Further, the cooling water flows into the main body from a cooling water circuit (not shown) connected to the connection port 10 of the main body 1, and is guided by the partition plates 5, 5 and flows through the connection port 12 without stagnation. From the cooling water circuit (not shown).

At this time, since the cooling water is guided by the partition plate 5, the cooling water passes uniformly around the tube 2 without stagnation at one place, so that the cooling efficiency is high.

When the notch 7 of the partition plate 5 comes to the upper part, it serves as an air passage. For example, as shown in FIG. The air 17 remaining in the corner at 14 is at a higher position than the tube 2 at the highest position, and the tube 2 is located in the cooling water W, so that it is not damaged.

This will be described in more detail with reference to FIG. In the illustrated embodiment, the tube 2 is not provided above the tube sheet 15. Assuming that a virtual tube 2G as shown by a dotted line in FIG. 3 is provided, as apparent from FIG. 3, the virtual tube 2G is connected to the air 17 remaining in the main body in the vicinity of the connection point with the tube sheet 15. Contact. Then, in the virtual tube 2G,
It is considered that the portion that has come into contact with the air 17 cannot come into contact with the cooling water, remains exposed to the hot EGR gas, and eventually breaks. Here, a tube (a tube like a virtual tube 2G shown in FIG. 3) that may come into contact with the air 17 (shown by hatching in FIG. 3) remaining in the main body is provided at an upper portion of the tube sheet 15. Tube connected to the area. Therefore, unless the tube is connected to the upper region of the tube sheet 15, the tube 2 is prevented from being damaged by contact with the air 17 remaining in the main body. In other words, tube sheet 1
In the upper part of 5, the area where the tube 2 is not connected is determined by the size of the area where the air (17) remains in the main body, and the area where the air (17) remains in the main body depends on the position of the air vent 14, It is determined from the inclination angle of the EGR cooler and the like. Although the partition plate 5 and the baffle are provided in FIG. 3, they can be omitted.

The space 8 formed between the notch 7 of the partition plate 5 mounted on the lower side and the main body 1 has an effect of preventing the cooling water flow of the main body 1 from stagnation.

FIG. 4 and FIG. 5 show another embodiment of the present invention.
Is the same as that of the first embodiment except that the position is slightly inclined with respect to the vertical direction of the EGR cooler main body.
Since it is provided at the upper position in the vertical direction of the cooler main body), the effect of increasing the degree of freedom in layout can be expected by inclining the connection ports 10 and 12 of the cooling water.

[0022]

The present invention is constructed as described above. By providing the partition plate, the flow of the cooling water becomes smooth, the cooling efficiency is improved, the vibration resistance is enhanced, and the partition plate is provided with a notch. By providing air, air bleeding is ensured, and stagnation of the cooling water is further reduced, so that the durability and the performance of the cooler device are improved.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a view for explaining the operation and effect of FIG. 1;

FIG. 4 is a diagram showing another embodiment of the present invention.

FIG. 5 is a view taken in the direction of arrow B in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main body 2 ... Tube 3 ... Connection fitting 4 ... Flange 5 ... Partition plate 7 ... Notch part 10, 12 ... Connection port 14 ... Air release port

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidefumi Fujiwara 1-chome, 1-chome, Ageo-shi, Saitama Nissan Diesel Industry Co., Ltd. Inside Nissan Diesel Industry Co., Ltd. (72) Inventor Motoharu Sugiyama 1719-1 Ooka, Numazu-shi, Shizuoka F-term (reference) 3G062 ED08 3L065 BA05 3L103 AA14 AA27 AA29 AA37 AA44 CC02 CC27 DD08 DD19 DD42 DD44 DD62

Claims (5)

[Claims] 1. A tube is fixed to a tube sheet having a large number of holes provided at both ends of a tubular body, and connection fittings for connecting a gas circuit are provided at both ends of the tubular body.
A connection port is provided on the outer periphery for connection to the cooling water circuit.
In the GR cooler device, a plurality of partition plates are attached between the tube sheets, and the partition plate is formed in a semicircular shape inscribed in the cylindrical body, and has a number of holes into which the tubes are inserted. An EGR cooler device comprising: 2. The EGR cooler device according to claim 1, wherein the plurality of partition plates are alternately arranged up and down such that straight portions face each other between the tube sheets. 3. The EGR cooler device according to claim 1, wherein a notch is provided in a part of a semicircle of the partition plate. 4. A tube is fixed to a tube sheet having a large number of holes provided at both ends of a cylindrical body, and connection fittings for connecting a gas circuit are provided at both ends of the cylindrical body.
A connection port is provided on the outer periphery for connection to the cooling water circuit.
In the GR cooler, on the top of the tube sheet,
An EGR cooler device characterized by having an area where a tube is not attached. 5. An air vent port is disposed vertically above the EGR cooler main body, and an inlet / outlet for cooling water is provided at a position inclined with respect to the vertical direction with respect to the air vent port. EGR cooler device.