阅读说明：本技术 膨胀箱 (Expansion tank ) 是由 小松周士 堀田直己 小出景二郎 下山伸次 福泽一郎 深田祐介 于 2021-03-24 设计创作，主要内容包括：一种膨胀箱,所述膨胀箱包括：箱主体,所述箱主体限定在其中储存冷却剂液体的储存室；多个分隔壁,所述多个分隔壁设置在所述箱主体中,以将所述储存室划分成包括入口室和出口室在内的多个分割室,所述多个分隔壁形成有连通孔,所述连通孔用于使所述多个分割室中的相邻分割室彼此连通；冷却剂液体入口部,所述冷却剂液体入口部设置在所述箱主体上并且通向所述入口室；冷却剂液体出口部,所述冷却剂液体出口部在形成在所述箱主体的底部内的凹部中具有出口开口并且通向所述出口室；以及屏障壁,所述屏障壁从所述箱主体的侧壁或所述多个分隔壁中的一个分隔壁延伸到所述凹部中。(An expansion tank, comprising: a tank body defining a storage chamber in which coolant liquid is stored; a plurality of partition walls provided in the box main body to divide the storage chamber into a plurality of divided chambers including an inlet chamber and an outlet chamber, the plurality of partition walls being formed with communication holes for communicating adjacent divided chambers of the plurality of divided chambers with each other; a coolant liquid inlet portion provided on the tank main body and opening into the inlet chamber; a coolant liquid outlet portion having an outlet opening in a recess formed in the bottom of the tank main body and opening into the outlet chamber; and a barrier wall extending from a side wall of the tank main body or one of the partition walls into the recess.)

1. An expansion tank, comprising:

a tank body defining a storage chamber in which coolant liquid is stored;

a plurality of partition walls provided in the box main body to divide the storage chamber into a plurality of divided chambers including an inlet chamber and an outlet chamber, the plurality of partition walls being formed with communication holes for communicating adjacent divided chambers of the plurality of divided chambers with each other;

a coolant liquid inlet portion provided on the tank main body and opening into the inlet chamber;

a coolant liquid outlet portion having an outlet opening in a recess formed in the bottom of the tank main body and opening into the outlet chamber; and

a barrier wall extending from a side wall of the tank main body or one of the plurality of partition walls into the recess.

2. The expansion tank of claim 1, wherein the barrier wall extends in a direction across the outlet opening.

3. The expansion tank according to claim 1 or 2, wherein the outlet chamber communicates with at least two divided chambers adjacent to the outlet chamber via communication holes formed in partition walls separating the outlet chamber from the divided chambers, and the communication holes to the outlet chamber include communication holes positioned on both sides of the barrier wall.

4. The expansion tank according to claim 1 or 2, wherein the barrier wall extends at least to a height substantially corresponding to the lowest level of the coolant liquid stored in the storage chamber.

5. The expansion tank according to claim 1 or 2, wherein the recess is defined by a portion of the bottom wall of the tank main body that is inclined downward toward a central portion of the recess, and

the coolant liquid outlet portion includes a coolant liquid outlet pipe extending from the outlet opening to the outside of the tank main body in an oblique direction of the portion of the bottom wall.

Technical Field

The present invention relates to an expansion tank, and more particularly to an expansion tank used in a cooling system of an internal combustion engine.

Background

An expansion tank used in a cooling system of an internal combustion engine is connected to a coolant liquid circulation passage including a radiator and the like, and is configured to absorb a volume fluctuation of coolant liquid due to a temperature change by allowing the coolant liquid to enter and exit the expansion tank as needed. Known expansion tanks of this type comprise: a tank body defining a storage chamber for storing a coolant liquid therein; a plurality of partition walls provided in the box main body to divide the storage chamber into a plurality of divided chambers including an inlet chamber and an outlet chamber, the partition walls being formed with communication holes for communicating adjacent divided chambers with each other; a coolant liquid inlet provided in the tank main body to open to the inlet chamber; and a coolant liquid outlet provided in the tank main body to open to the outlet chamber (for example, JP6461364B 2).

In such an expansion tank, when the coolant liquid flows out from the coolant liquid outlet to the coolant liquid circulation passage, a vortex of the coolant liquid called a bathtub vortex tends to be generated above the coolant liquid outlet, the vortex is generated substantially around the coolant liquid outlet, and a portion of the liquid surface above the coolant liquid outlet is caused to be depressed in an approximately conical shape, and therefore when the liquid level in the storage chamber is low, air may be entrained in the coolant liquid, so that many air bubbles can flow into the coolant liquid circulation passage.

To solve this problem, JP2019-60275A discloses a reserve tank having a rib wall provided in a tank main body such that a flow of coolant liquid collides with the rib wall. This reduces the flow rate of the coolant liquid, thereby inhibiting entrainment of air into the coolant liquid flowing from the storage chamber to the coolant liquid outlet. Furthermore, JP2017-78399A discloses an expansion tank which is internally provided with a tubular portion at a position above a coolant liquid outlet, wherein the tubular portion has a lower end opened toward the coolant liquid outlet, so that a reduction in the internal pressure in the tubular portion suppresses the generation of eddy currents of the coolant liquid at the coolant liquid outlet.

However, in the conventional reserve tank or expansion tank, it is difficult to sufficiently suppress the vortex flow of the coolant liquid generated above the coolant liquid outlet, and there is a restriction that suppresses the flow of bubbles into the coolant liquid circulation passage.

Disclosure of Invention

An object of the present invention is to provide an expansion tank capable of effectively suppressing generation of a vortex of coolant liquid in the vicinity of a coolant liquid outlet, thereby effectively suppressing inflow of bubbles into a coolant liquid circulation passage.

One embodiment of the present invention provides an expansion tank 10 comprising: a tank body 18 defining a storage chamber 16 in which coolant liquid is stored; a plurality of partition walls 40, 42, 44, 46, 48, 50, 52 provided in the tank main body to divide the storage chamber into a plurality of divided chambers 38 including the inlet chamber 34 and the outlet chamber 36, the plurality of partition walls being formed with communication holes 54 for communicating adjacent divided chambers of the plurality of divided chambers with each other; a coolant liquid inlet portion 28 provided on the tank main body and opening into the inlet chamber; a coolant liquid outlet 60 having an outlet opening 62 in the recess 56 formed in the bottom of the tank body and opening into the outlet chamber; and a barrier wall 66 extending from the side wall 32 of the tank main body or one of the partition walls into the recess.

According to this configuration, the barrier wall suppresses generation of a vortex of the coolant liquid in the vicinity of the coolant liquid outlet.

In the above expansion tank, preferably, the barrier wall extends in a direction crossing the outlet opening.

According to this configuration, the barrier wall effectively suppresses generation of a vortex of the coolant liquid in the vicinity of the coolant liquid outlet.

In the above expansion tank, preferably, the outlet chamber communicates with at least two divided chambers adjacent to the outlet chamber via communication holes formed in partition walls separating the outlet chamber from the divided chambers, and the communication holes leading to the outlet chamber include communication holes positioned on both sides of the barrier wall.

According to this configuration, generation of a vortex of the coolant liquid in the vicinity of the coolant liquid outlet is suppressed due to at least two flows of the coolant liquid flowing into the outlet chamber via the communication hole.

In the above expansion tank, preferably, the barrier wall extends at least to a height substantially corresponding to a minimum level of the coolant liquid stored in the storage chamber.

According to this configuration, even if the level of the coolant liquid stored in the storage chamber becomes the lowest level, the barrier wall can exhibit the effect of suppressing the vortex of the coolant liquid.

In the above expansion tank, preferably, the recess is defined by a portion 56B of the bottom wall of the tank main body that is inclined downward toward a central portion 56A of the recess, and the coolant liquid outlet portion includes a coolant liquid outlet pipe 64 that extends from the outlet opening to the outside of the tank main body in the direction of inclination of the portion of the bottom wall.

According to this configuration, the coolant liquid flowing out of the tank from the recess portion via the coolant liquid outlet portion can flow smoothly.

The expansion tank according to one embodiment of the present invention can effectively suppress the generation of the vortex of the coolant liquid in the vicinity of the coolant liquid outlet, thereby effectively suppressing the flow of bubbles into the coolant liquid circulation passage.

Drawings

Fig. 1 is a perspective view showing one embodiment of an expansion tank according to the present invention;

fig. 2 is a plan view of the lower tank member of the expansion tank of the embodiment;

FIG. 3 is a horizontal sectional view of the lower tank member; and

fig. 4 is an enlarged vertical sectional view (an enlarged sectional view taken along line IV-IV in fig. 2) of a main portion of the lower tank member.

Detailed Description

Hereinafter, one embodiment of the expansion tank according to the present invention will be described with reference to fig. 1 to 4.

As shown in fig. 1, the expansion tank 10 of the present embodiment includes a tank main body 18 constituted by a lower tank member 12 and an upper tank member 14 which are airtightly joined to each other and each made of resin. The tank main body 18 defines a storage chamber 16 (see fig. 2) in which coolant liquid is stored. A cap 20 equipped with a relief valve and an exhaust pipe 22 is attached to the upper tank member 14.

The upper tank member 14 is provided with a coolant liquid inlet portion 28 and a coolant liquid inlet pipe 26, the coolant liquid inlet portion 28 including an inlet opening 24 leading to an inlet chamber 34 described later, the coolant liquid inlet pipe 26 communicating with the inlet opening 24 and extending to the outside of the tank main body 18.

As shown in fig. 2 and 3, the lower tank member 12 has a bottom wall 30 and a side wall 32, the side wall 32 extending along an outer edge of the bottom wall 30 and standing upright from the outer edge, whereby the lower tank member 12 assumes a box-like shape with an open top.

In the lower tank member 12, a plurality of partition walls 40, 42, 44, 46, 48, 50, 52 are provided to divide the reservoir chamber 16 into a plurality of divided chambers 38 including the inlet chamber 34 and the outlet chamber 36. The lower portions of the partition walls 40, 42, 44, 46, 48, 50, 52 are formed with communication holes 54 for communicating the adjacent divided chambers 38 (such as the inlet chamber 34 and the outlet chamber 36) with each other.

A portion of the bottom wall 30 of the lower tank member 12 corresponding to the outlet chamber 36 (in other words, a portion of the bottom wall 30 defining the bottom of the outlet chamber 36) is formed with a recess 56. As shown in fig. 4, the recess 56 includes: a gentle slope 56B that is located on one side of a central portion (deepest portion) 56A of the recess 56 and is inclined downward toward the central portion 56A; and a steep slope 56C which is located on the other side of the central portion (deepest portion) 56A and is inclined downward toward the central portion 56A, whereby the recess 56 has a substantially triangular cross-sectional shape.

The lower tank member 12 has a coolant liquid outlet 60 formed in the bottom thereof. The coolant liquid outlet portion 60 includes an outlet opening 62 and a coolant liquid outlet pipe 64, the outlet opening 62 opening at the steep slope 56C of the recess 56, the coolant liquid outlet pipe 64 extending from the outlet opening 62 to the outside of the lower tank member 12 along the inclination direction of the gentle slope 56B. The coolant liquid outlet portion 60 is thereby opened to the outlet chamber 36 in the recess 56.

The lower tank member 12 is formed with a barrier wall 66, the barrier wall 66 being provided on a surface of the partition wall 40 facing the outlet chamber 36 and extending into the recess 56 in plan view, as shown in fig. 2 and 3. As shown in fig. 4, the barrier wall 66 has a flat plate shape that vertically extends from a portion of the bottom wall 30 of the lower tank member 12 that includes the gentle slope 56B of the recess 56 to a height corresponding to the minimum level Lmin of the coolant liquid stored in the storage chamber 16 (outlet chamber 36). The barrier wall 66 also extends in a direction across the outlet opening 62 as seen in plan view, in other words, in a direction that divides the outlet opening 62 into two.

The recess 56 and the barrier wall 66 are arranged in the vicinity of the communication hole 54, which communication hole 54 is formed in the partition wall 46 to communicate the outlet chamber 36 and the partition chamber 38 adjacent to the outlet chamber 36 with each other. The communication holes 54 of the partition walls 46 open toward one surface of the barrier wall 66.

The outlet chamber 36 adjoins the inlet chamber 34 and the two divided chambers 38, and communicates with the inlet chamber 34 and the two divided chambers 38 via communication holes 54 formed in partition walls 40, 46, 52 that separate the inlet chamber 34 and the two divided chambers 38 from the outlet chamber 36, respectively. The communication hole 54 of the partition wall 46 that opens into the outlet chamber 36 is positioned on the opposite side of the barrier wall 66 from the side where the communication holes 54 of the partition walls 40 and 52 also open into the outlet chamber 36.

In the expansion tank 10 according to the above embodiment, the barrier wall 66 extends to traverse a vortex of coolant liquid ("bathtub vortex") that may be generated substantially around the outlet opening 62 when coolant liquid stored in the storage chamber 16 flows out of the tank from the outlet chamber 36 via the coolant liquid outlet 60 without the barrier wall 66. That is, the barrier wall 66 functions as a baffle to effectively suppress the generation of the vortex.

Therefore, it is possible to effectively suppress the inflow of air bubbles into the coolant liquid circulation passage (not shown) of the engine cooling system connected to the expansion tank 10, so that it is possible to suppress the cavitation of the cooling pump (not shown) of the engine cooling system.

Since the barrier wall 66 extends to a height corresponding to the minimum level Lmin of the coolant liquid stored in the outlet chamber 36, the barrier wall 66 can effectively exhibit the above-described vortex suppression effect even if the level of the coolant liquid stored in the outlet chamber 36 becomes the minimum level Lmin.

The communication holes 54 of the partition wall 46 and the communication holes 54 of the partition walls 40 and 52 (all open to the outlet chamber 36) are positioned on both sides of the barrier wall 66, whereby the coolant liquid flowing into the outlet chamber 36 via the communication holes 54 of the partition wall 46 and the coolant liquid flowing into the outlet chamber 36 via each of the communication holes 54 of the partition walls 40 and 52 collide with each other near the barrier wall 66. This also helps to suppress the generation of eddy currents in the vicinity of the outlet opening 62.

Since the coolant liquid outlet pipe 64 of the coolant liquid outlet port 60 extends from the outlet opening 62 to the outside of the lower tank member 12 along the inclined direction of the gentle slope 56B of the recessed portion 56, the coolant liquid flowing out of the tank from the recessed portion 56 via the coolant liquid outlet port 60 can smoothly flow with low flow resistance. This prevents the occurrence of turbulence in the coolant liquid flowing out of the tank, thereby suppressing mixing of bubbles into the coolant liquid flowing out of the tank from the coolant liquid outlet portion 60.

Although the present invention has been described according to the preferred embodiments thereof, it is apparent to those skilled in the art that the present invention is not limited to these embodiments, but can be modified without departing from the spirit of the invention. For example, the barrier wall 66 may extend from the side wall 32 of the lower tank member 12 instead of a partition wall such as the partition wall 40. Although the coolant liquid outlet 60 is inclined with respect to the bottom of the lower tank member 12 in the illustrated embodiment, the coolant liquid outlet 60 may extend vertically downward from the bottom of the lower tank member 12. In the illustrated embodiment, the barrier wall 66 is connected to the bottom wall 30 of the lower tank member 12, but in another embodiment, the barrier wall 66 may be spaced apart from the bottom wall 30. Further, various components shown in the above-described embodiments are not necessarily all necessary, and may be appropriately selected and replaced without departing from the spirit of the present invention.