Patent Description:
Heat generated from various heat sources such as IGBT modules or thyristors used in power devices must be removed to prevent heat sources from being damaged by heat, such that the operating efficiency and durability of power devices are improved.

Related art <NUM> discloses an evaporator for vaporizing working fluid with heat transferred from a heat source in a loop-type heat pipe. However, since the working fluid flows through a plurality of flow paths in the evaporator disclosed in the related art <NUM>, there is a risk of a lot of leakage, and the vapor does not flow smoothly inside the evaporator.

In addition, in the Related art <NUM>, the working fluid is not uniformly delivered to a wick that generates the capillary action, so the movement of the working fluid by the capillary action and the evaporating action thereof are not relatively smooth.

<CIT> discloses a cooling device which is provided with an evaporator with a built-in wick, a condenser, and a loop type heat pipe which connects the evaporator and condenser in a loop and is provided with a liquid pipe and vapor pipe, wherein the evaporator is divided into a liquid-pipe-side case and a vapor-pipe-side case and wherein a plurality of discharge ports of working fluids and a wick in which the working fluid from the discharge ports is completely permeated are arranged between the two cases. The wick is provided with projecting parts which have recessed parts corresponding to the discharge ports, while the outer circumferential surfaces of the projecting parts are provided with grooves. The working fluid which permeates the wick is changed to a vapor inside the vapor-pipe-side case, collects in the evaporation chamber, and is discharged to the liquid pipe, and thus, dry out of the wick is prevented.

<CIT> discloses a loop type heat pipe, in which a part of working fluid evaporated in an evaporation chamber through an additional bypass connecting pipe is moved to a condensed water chamber in a steam state, thereby inducing a smooth flow of condensed water by preventing an excessive steam pressure in the evaporation chamber. Furthermore, the working fluid in the steam state is supplied from the evaporation chamber to a lower space of the condensed water chamber through the bypass connecting pipe, and a punched board is located at an upper portion thereof for the steam supplied to the condensed water chamber to pass through a steam flow hole of the punched board while providing a rising pressure to the condensed water in a dynamic state which is stored in the condensed water chamber, and inducing a dynamic state of the condensed water by generating bubbles, thereby smoothly inducing the condensed water to be absorbed to a wick, and thus maintaining a stable operating state.

<CIT> discloses a cooling apparatus of a looped heat pipe structure.

<CIT> discloses a semiconductor package, a cooling mechanism and a method for manufacturing a semiconductor package.

The objective of the present disclosure is to solve the problems of the related arts as described above, such that working fluid that performs a cooling action while flowing in a heat pipe is smoothly transferred to an evaporation device.

Another objective of the present disclosure is to allow the working fluid to be evaporated by spreading over a wide area by capillary action and in the evaporation device.

Further, another objective of the present disclosure is to uniformly exchange heat with a heat source in the entire interior of the evaporation device.

The invention provides a evaporation device according to claim <NUM>.

An evaporation device for cooling according to the present disclosure may obtain at least one or more of the following effects.

In the present disclosure, a distributor may be installed to mix a working fluid introduced from the outside of the housing by capillary force with an existing working fluid filled at a predetermined level in the lower part of the evaporation space inside the housing. The distributor is made of, for example, a screen wick to move the working fluid by capillary force to mix with the existing working fluid in the evaporation space. Accordingly, the working fluid may be smoothly transferred to the evaporation space of the evaporation device.

In the present disclosure, the wick may be installed on the inner surface corresponding to the outer surface in contact with a heat source among the inner surfaces of the housing, such that the working fluid moving along the wick may be easily evaporated by the heat transferred from the heat source, thereby smoothly dissipating heat.

In the present disclosure, as the vapor generated by evaporation of the working fluid moves toward a vapor outlet pipe, the flow rate and flow velocity of the vapor may be adjusted to decrease relatively so that heat exchange may occur uniformly in the entire area of the wick. Therefore, there is an effect that the heat dissipation generated from the heat source may be uniformly performed as a whole.

In addition, in the present disclosure, the movement of the working fluid is based on the principle of the heat pipe, such that additional power may not be consumed to circulate the working fluid, thereby improving the efficiency of the related power device.

Hereinafter, some embodiments of the present disclosure will be described in detail with reference to exemplary drawings. In assigning reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though the same components are indicated on different drawings. In addition, in describing the embodiment of the present disclosure, if it is determined that a detailed description of a related known configuration or function interferes with the understanding of the embodiment of the present disclosure, the detailed description thereof will be omitted.

In addition, in describing the components of the embodiment of the present disclosure, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only used to distinguish between the components, and the nature, or order of the components are not limited by the terms. When a component is described as being "combined with", "coupled to" or "connected to" another component, the component may be directly connected to or combined with each other, but it should be understood that another component may be "connected to", "coupled to" or " combined with" each of the components therebetween.

As shown in the drawings, an evaporation device for cooling of the embodiment of the present disclosure is a device in which a working fluid is evaporated by receiving heat from a heat source. The working fluid may discharge heat from a separate condensing unit to the outside, while passing through a working fluid inlet pipe <NUM> and a vapor outlet pipe <NUM> to be described below. A housing <NUM> may form the exterior of the evaporation device for cooling of the present disclosure. The housing <NUM> may have a flat hexahedral shape, and be erected so that a face having a relatively large area is viewed in a horizontal direction. An outer surface of one side of the housing <NUM> may be installed and used to be in contact with a heat source (not shown). A plurality of protrusions and grooves may be formed on the inside of the housing <NUM>, that is, on an inner surface of the housing <NUM> to promote the working fluid nucleate boiling.

The housing <NUM> may include an evaporation space <NUM> therein. In the evaporation space <NUM>, the working fluid may be evaporated by receiving heat from the heat source. The lower portion of the evaporation space <NUM> may be filled with the working fluid to a predetermined level when the evaporation device for cooling is operated. The amount of working fluid to be filled should be at least enough to submerge a distributor <NUM>, which will be described below.

The evaporation space <NUM> may be shielded from the outside by a cover <NUM> constituting a part of the housing <NUM>. The cover <NUM> may shield the evaporation space <NUM> from the outside while forming a surface having a relatively large area of the housing <NUM>. The surface that the cover <NUM> shields may be an opposite surface facing the surface that the heat source is in contact with. A plurality of protrusions and grooves for promoting nucleate boiling of the working fluid may be formed on the inner surface of the cover <NUM>.

A wick <NUM> may be installed on an inner surface of the evaporation space <NUM> of the housing <NUM>. The wick <NUM> may serve to move the working fluid from a lower portion of the evaporation space <NUM> to an upper portion thereof by using the capillary force. As described above, the heat source may be in contact with the surface of the housing <NUM> facing the cover <NUM>, and heat is transferred to the evaporation space <NUM> through the housing <NUM>. Accordingly, the wick <NUM> may be entirely installed on the inner surface corresponding to the outer surface of the housing <NUM> in contact with the heat source. A variety of wicks <NUM> may be used. In the illustrated embodiment, a screen wick in the form of a mesh net may be used. The wick <NUM> may serve to move the working fluid by capillary action, and may move the working fluid from a lower portion of the evaporation space <NUM> to an upper portion thereof.

The wick <NUM> may be installed on an inner surface of the housing <NUM> such that the working fluid may move to an upper portion of the evaporation space <NUM> by capillary force of the wick. In such process, the working fluid may be uniformly evaporated in the entire area of the evaporation space <NUM> to become a gas by the heat from the heat source. To this end, the wick <NUM> may be positioned on the entire inner surface of the housing <NUM> with the largest area.

When a screen wick is used as the wick <NUM>, a protection plate <NUM> may be installed to protect and fix the wick <NUM> at the same time. The protection plate <NUM> may maintain the shape of the wick <NUM> without being damaged by a partition wall <NUM>(described below), and allow the wick <NUM> to be fixedly installed. The protection plate <NUM> may have the same structure as the wick <NUM>, but have a less tight mesh structure than the mesh structure of the wick <NUM>. Accordingly, the protection plate <NUM> may protect the first wick <NUM>, and at the same time may also partially serve to move the working fluid to the upper portion of the evaporation space by capillary force.

For reference, various types of wicks may be used as the wick <NUM>. A screen wick is used as an example in this embodiment. However, a sintered metal wick may be used or a groove wick formed on the inner surface of the housing <NUM> may be used.

A partition wall <NUM> may be installed in the evaporation space <NUM>. The partition wall <NUM> may divide the evaporation space <NUM> into a plurality of spaces communicating with each other. The partition wall <NUM> may also serve to press the protection plate <NUM> to fix the protection plate <NUM> in the evaporation space <NUM>. The partition wall <NUM> may be installed to be press-fitted into the housing <NUM> and may press the protection plate <NUM> to be fixed. Of course, the partition wall <NUM> may be fastened to the housing <NUM> using a fastening means.

In the partition wall <NUM>, a partition wall body part <NUM> having a band-shaped plate shape forms an exterior of the partition wall <NUM>, and a plurality of communication parts <NUM> are formed in the partition wall body part <NUM> to allow spaces partitioned by the partition wall <NUM> to communicate with each other. The partition wall body part <NUM> is orthogonally coupled to each other by coupling slots (reference numerals not assigned) formed at positions corresponding to each other and positioned in the evaporation space <NUM> in a grid shape. As shown in <FIG>, the front end of the partition wall <NUM> may be in close contact with the cover <NUM>. In this way, the partition wall <NUM> may be fixed in the housing <NUM> without an additional fastening means.

The communication part <NUM> formed in the partition wall <NUM> allows spaces partitioned by the partition wall <NUM> to communicate with each other. The amount of vapor flowing between the partitioned spaces may be determined according to the area of the communication part <NUM>. In other words, the area of the communication part <NUM> may vary the speed and amount of vapor flowing, so that the degree of dissipating the heat generated from the heat source by the working fluid may be varied. In general, the flow of vapor becomes faster in a region close to the vapor outlet pipe <NUM>. Therefore, heat may be well dissipated in the region adjacent to the vapor outlet pipe <NUM>, but in the region adjacent to the working fluid inlet pipe <NUM>, the flow of vapor is inevitably slow, so the heat dissipation amount may be relatively small. In this case, when viewed over the entire area of the evaporation space <NUM>, heat dissipation may occur non-uniformly. Referring to <FIG>, the amount of heat dissipation from the upper-right region of the evaporation space <NUM> may be small, and the amount of heat dissipation from the upper-left region of the evaporation space <NUM> may be large.

Accordingly, it is preferable that the area of the communication part <NUM> may be relatively small in the region adjacent to the vapor outlet pipe <NUM>, and the area of the communication part <NUM> may be relatively large in the region adjacent to the working fluid inlet pipe <NUM>.

Such a structure may ensure uniformity of heat dissipation by controlling the speed and amount of vapor flow, which may be performed in other ways. That is, even if an area of the communication part <NUM> is the same, the size of the spaces divided by the partition wall <NUM> may be relatively narrow in the region adjacent to the vapor outlet pipe <NUM>, and relatively wide in the region adjacent to the working fluid inlet pipe <NUM>. In such a way, the speed and amount of vapor flow may be controlled. To this end, the size of the space partitioned by the partition wall <NUM> may be adjusted depending on the location, or while the horizontal and vertical intervals of the partition walls <NUM> are the same as in the illustrated embodiment, an additional partition wall <NUM> may be installed between the partition walls <NUM>, thereby controlling the flow speed and amount of vapor.

Meanwhile, the working fluid inlet pipe <NUM> for supplying the working fluid to the evaporation space <NUM> of the housing <NUM> from the outside is provided. The working fluid inlet pipe <NUM> is installed on a lower portion of the housing <NUM> in the gravitational direction, passing through the housing <NUM>, as shown in <FIG> and <FIG>. The working fluid inlet pipe <NUM> communicates with a lower portion of the evaporation space <NUM>.

To discharge the vapor produced in the evaporation space <NUM> of the housing <NUM> to the outside, the vapor outlet pipe <NUM> is connected to an upper portion of the housing <NUM> in the gravitational direction. That is, compared to the working fluid inlet pipe <NUM>, the vapor outlet pipe <NUM> is relatively higher in the gravitational direction. The vapor outlet pipe <NUM> communicates with the upper portion of the evaporation space <NUM>.

The distributor <NUM> may be installed in a lower portion of the evaporation space <NUM> connected to the working fluid inlet pipe <NUM>. The distributor <NUM> may serve to uniformly transfer the working fluid introduced through the working fluid inlet pipe <NUM> to the entire lower portion of the evaporation space <NUM>. The working fluid introduced through the working fluid inlet pipe <NUM> may have a lower temperature than the existing working fluid in the evaporation space <NUM>. Accordingly, the working fluid introduced through the working fluid inlet pipe <NUM> may be uniformly mixed with the existing working fluid filled in the lower portion of the evaporation space <NUM> and may be transferred to the evaporation space <NUM> through the wick <NUM>, so that the working fluid may uniformly receive the heat from the heat source throughout the evaporation space <NUM>.

The distributor <NUM> may be, for example, a hollow cylindrical shape by rolling the screen wick, or a columnar shape with a denser inside by tightly rolling the screen wick. That is, when the distributor <NUM> is formed in a hollow cylindrical shape, the working fluid introduced through the working fluid inlet pipe <NUM> may be moved through the inside of the cylindrical screen wick, and at the same time, may be quickly transferred to the front end of the distributor <NUM> through the capillary action generated from the screen wick. When the screen wick is tightly rolled to form a columnar shape, the working fluid may flow through the inside of the distributor <NUM> and move by the capillary action occurring in the screen wick.

Hereinafter, the use of the evaporation device for cooling according to the present disclosure having the above-described configuration will be described in detail.

When the evaporation device for cooling of the present disclosure is used, the working fluid may be pre-filled to the extent that the distributor <NUM> is submerged in the inside of the evaporation space <NUM>.

Heat may be transferred from the heat source in contact with the rear surface of the housing <NUM> as indicated by arrow A. In addition, the working fluid filled in the evaporation space <NUM> may move to the upper portion of the evaporation space <NUM> by the wick <NUM> as indicated by arrow B.

When the working fluid moves along the wick <NUM> by capillary force and absorbs heat transferred from the heat source, the working fluid may become a gas and move to the spaces partitioned by the partition walls <NUM>, as indicated by arrow C. In the evaporation space <NUM>, the vapor may flow toward the vapor outlet pipe <NUM>.

As the vapor flows toward the vapor outlet pipe <NUM>, the flow speed and flow amount may be controlled by the partition wall <NUM>, etc. The flow speed and flow amount may be relatively reduced toward the vapor outlet pipe <NUM>, while the flow speed and flow amount may be relatively increased toward the working fluid inlet pipe <NUM>, so that the (generated) heat may be transferred to the working fluid as uniformly as possible and dissipated efficiently.

Meanwhile, the working fluid transferred from a condensing unit (not shown) through the working fluid inlet pipe <NUM> may be distributed in the working fluid in the lower portion of the evaporation space <NUM> by the distributor <NUM>. The distributor <NUM> may generate the capillary action so that the working fluid may move from the working fluid inlet pipe <NUM> to the front end of the distributor <NUM> to be mixed with the existing working fluid pre-filled in the evaporation space <NUM>. Accordingly, the working fluid having a relatively low temperature may be uniformly mixed with the existing working fluid having a relatively high temperature in the evaporation space <NUM>, and thus the working fluid may receive the heat transferred from the heat source uniformly as a whole.

Claim 1:
An evaporation device for cooling comprising:
a housing (<NUM>) in which an evaporation space (<NUM>) is formed and a heat source is in contact with an outer surface of one side thereof, and the housing (<NUM>) being connected to a working fluid inlet pipe (<NUM>) on one side and a vapor outlet pipe (<NUM>) on another side thereof, and a working fluid is filled with a predetermined level therein;
a wick (<NUM>) installed on an inner surface corresponding to the heat source among the inner surfaces of the evaporation space (<NUM>) to generate movement of the working fluid by capillary action;
a partition wall (<NUM>) dividing the evaporation space (<NUM>) into a plurality of spaces communicating with each other and supporting the wick (<NUM>); and
a distributor (<NUM>) installed extending to the opposite side of the working fluid inlet pipe (<NUM>) to mix the working fluid introduced through the working fluid inlet pipe (<NUM>) with the working fluid pre-filled in the evaporation space (<NUM>),
wherein the working fluid inlet pipe (<NUM>) is connected to a lower portion of one side of the housing (<NUM>) in a gravitational direction, and the vapor outlet pipe (<NUM>) is connected to an upper portion of one side of the housing (<NUM>) in a gravitational direction, and
wherein the partition wall (<NUM>) has a communication part (<NUM>) formed in the partition wall body part (<NUM>) having a band shape, the partition wall body part (<NUM>) is orthogonally coupled to each other by coupling slots formed at positions corresponding to each other and positioned in the evaporation space (<NUM>) in a grid shape, and the vapor flows between the spaces partitioned by the partition wall (<NUM>) through the communication part (<NUM>).