Patent Description:
Heat exchange ventilators, in which heat exchange between a supply air flow from the outside to the inside of a room and an exhaust air flow from the inside to the outside of the room is carried out, have been known. Ventilation using a heat exchanging element can improve the efficiency of heating and cooling the inside of a room to reduce energy used for air conditioning of the room, and maintain a good air quality inside the room.

A typical heat exchanging element includes sheet materials for separating a passage through which a supply air flow passes and a passage through which an exhaust air flow passes from each other, and a holding member for keeping distances between the sheet materials. It is desired that a heat exchanging element can efficiently transfer heat between passages to improve the heat exchange efficiency.

Examples of known types of heat exchanging elements through which a supply air flow and an exhaust air flow pass include a crossflow type and a counterflow type. In the crossflow type, the direction of a supply air flow passing through the heat exchanging element and the direction of an exhaust air flow passing through the heat exchanging element are perpendicular to each other. In the counterflow type, the direction of a supply air flow passing through the heat exchanging element and the direction of an exhaust air flow passing through the heat exchanging element are opposite each other. Under a condition where pressure losses are equal to each other, a counterflow heat exchanging element theoretically has a higher heat exchange efficiency per unit volume than a crossflow heat exchanging element. Thus, heat exchanging elements of counterflow type are used in many conventional heat exchange ventilators.

Patent Literature <NUM> teaches a heat exchanging element including a plurality of passages formed of sheet materials, in which the passages have quadrangular cross sections. The sheet materials serve to separate adjacent passages from each other. In the heat exchanging element according to Patent Literature <NUM>, heat exchange between air flows can be carried out over the entire surfaces of the passages, which can increase the heat exchange amount. In addition, in the heat exchanging element according to Patent Literature <NUM>, because the passages have quadrangular cross sections, the passages are less likely to be deformed in a state in which the layers of sheet materials are stacked, which can reduce the pressure loss. Furthermore, because the passages are formed only of sheet materials, the heat exchanging element according to Patent Literature <NUM> can reduce the number of components.

In the conventional heat exchanging element taught in Patent Literature <NUM>, there may be an attempt to increase the sheet materials to be stacked as a means for further improving the heat exchange efficiency. There is, however, a limit to the increase the sheet materials in order to accommodate the heat exchanging element in the heat exchange ventilator, because such increase of the sheet materials results in increase of the size of the heat exchanging element. In order to increase the sheet materials without making the heat exchanging element larger, it can be considered to decrease the cross-sectional areas of the passages. In this case, there is a problem in that the pressure loss increases.

The present disclosure has been made in view of the above, and an object thereof is to provide a heat exchanging element capable of improving heat exchange efficiency.

To solve the aforementioned problems and achieve the object, a heat exchanging element according to the present disclosure includes a first passage forming member and a second passage forming member stacked alternately, the heat exchanging element including a counterflow part that includes a first passage through which air passes and a second passage through which air flows in a direction opposite a direction in which the air passes through the first passage. The first passage forming member and the second passage forming member each include: a rib portion, which constitutes the counterflow part, including a first wall portion constituting an end in a first direction of the first passage, a second wall portion constituting an end in the first direction of the second passage, and a third wall portion separating the first passage and the second passage adjacent to each other in a second direction from each other, the first direction being a direction in which the first passage forming member and the second passage forming member are stacked, the second direction being perpendicular to the first direction. The first passage forming member and the second passage forming member each include: a board being in contact with an end in a third direction of the rib portion, and separating a first connection passage communicating with the first passage and a second connection passage communicating with the second passage from each other, the third direction being perpendicular to the first direction and to the second direction; a first blocking portion installed at the end of the rib portion, to block between the first passage and the second connection passage; and a second blocking portion installed at the end of the rib portion, to block between the second passage and the first connection passage.

A heat exchanging element according to the present disclosure produces an effect of enabling improvement in heat exchange efficiency.

A heat exchanging element and a heat exchange ventilator according to certain embodiments will be described in detail below with reference to the drawings.

<FIG> is a perspective view of an overall structure of a heat exchanging element according to a first embodiment. The heat exchanging element <NUM> according to the first embodiment is a counterflow heat exchanging element. The heat exchanging element <NUM> is a layered structure including first passage forming members <NUM> and second passage forming members <NUM> that are alternately stacked. The number of first passage forming members <NUM> included in the heat exchanging element <NUM> and the number of second passage forming members <NUM> included in the heat exchanging element <NUM> each may be any numbers. In the description below, a stacking direction refers to a direction in which the first passage forming members <NUM> and the second passage forming members <NUM> are stacked.

The heat exchanging element <NUM> includes first passages and second passages. The first passage and the second passage are configured so that air passing through the first passage and air passing through the second passage do not mix with each other. In the first embodiment, the first passage is a supply air passage through which a supply air flow passes from the outside to the inside of a room. The second passage is an exhaust air passage through which an exhaust air flow passes from the inside to the outside of the room. The heat exchanging element <NUM> includes a counterflow part <NUM> in which heat exchange between the supply air flow and the exhaust air flow is carried out. The counterflow part <NUM> includes the first passage, and the second passage through which the exhaust air flow flows in a direction opposite to the supply air flow flowing through the first passage. Thus, in the counterflow part <NUM>, the flowing direction of the supply air flow and the flowing direction of the exhaust air flow are different from each other by <NUM> degrees.

<FIG> is a perspective view of a first passage forming member included in the heat exchanging element according to the first embodiment. <FIG> is a perspective view of a second passage forming member included in the heat exchanging element according to the first embodiment.

The first passage forming member <NUM> includes a first passage layer <NUM> that constitutes the counterflow part <NUM>, a first inlet header part <NUM>, and a first outlet header part <NUM>. The second passage forming member <NUM> includes a second passage layer <NUM> that constitutes the counterflow part <NUM>, a second inlet header part <NUM>, and a second outlet header part <NUM>. The counterflow part <NUM> is constituted by first passage layers <NUM> and second passage layers <NUM> that are alternately stacked.

The first inlet header part <NUM> includes a board <NUM>, and passage walls <NUM> installed to be raised on the board <NUM>. An end <NUM> of the board <NUM> constitutes an inlet of the supply air flow of the heat exchanging element <NUM>. The first inlet header part <NUM> constitutes an inlet-side passage between the inlet of the supply air flow and the counterflow part <NUM>. The passage walls <NUM> guide the supply air flow from the inlet of the supply air flow to the counterflow part <NUM>. The first outlet header part <NUM> includes a board <NUM>, and passage walls <NUM> installed to be raised on the board <NUM>. An end <NUM> of the board <NUM> constitutes an outlet of the supply air flow of the heat exchanging element <NUM>. The first outlet header part <NUM> constitutes an outlet-side passage between the outlet of the supply air flow and the counterflow part <NUM>. The passage walls <NUM> guide the supply air flow from the counterflow part <NUM> to the outlet of the supply air flow. In the first embodiment, each of the board <NUM> and the board <NUM> is a flat plate perpendicular to the stacking direction.

The second inlet header part <NUM> includes a board <NUM>, and passage walls <NUM> installed to be raised on the board <NUM>. An end <NUM> of the board <NUM> constitutes an inlet of the exhaust air flow of the heat exchanging element <NUM>. The second inlet header part <NUM> constitutes an inlet-side passage between the inlet of the exhaust air flow and the counterflow part <NUM>. The passage walls <NUM> guide the exhaust air flow from the inlet of the exhaust air flow to the counterflow part <NUM>. The second outlet header part <NUM> includes a board <NUM>, and passage walls <NUM> installed to be raised on the board <NUM>. An end <NUM> of the board <NUM> constitutes an outlet of the exhaust air flow of the heat exchanging element <NUM>. The second outlet header part <NUM> constitutes an outlet-side passage between the outlet of the exhaust air flow and the counterflow part <NUM>. The passage walls <NUM> guide the exhaust air flow from the counterflow part <NUM> to the outlet of the exhaust air flow. In the first embodiment, each of the board <NUM> and the board <NUM> is a flat plate perpendicular to the stacking direction.

First inlet header parts <NUM> and second outlet header parts <NUM> are alternately stacked. A face of the board <NUM>, which is opposite to the face on which the passage walls <NUM> are installed, covers the first inlet header part <NUM>, and thus forms the inlet-side passage for the supply air flow. A face of the board <NUM>, which is opposite to the face on which the passage walls <NUM> are installed, covers the second outlet header part <NUM>, and thus forms the outlet-side passage for the exhaust air flow.

First outlet header parts <NUM> and second inlet header parts <NUM> are alternately stacked. A face of the board <NUM>, which is opposite to the face on which the passage walls <NUM> are installed, covers the first outlet header part <NUM>, and thus forms the outlet-side passage for the supply air flow. A face of the board <NUM>, which is opposite to the face on which the passage walls <NUM> are installed, covers the second inlet header part <NUM>, and thus forms the inlet-side passage for the exhaust air flow.

<FIG> is a perspective view of the counterflow part of the heat exchanging element according to the first embodiment. <FIG> illustrates ends of the first passage layers <NUM> connected with the inlet-side passage for the supply air flow, and ends of the second passage layers <NUM> connected with the outlet-side passage for the exhaust air flow.

An X axis, a Y axis, and a Z axis are three axes that are perpendicular to each other. A Z-axis direction, which is a first direction, is the stacking direction. An X-axis direction, which is a second direction, is a direction perpendicular to the first direction. A Y-axis direction, which is a third direction, is a direction perpendicular to the first direction and to the second direction. The supply air flow and the exhaust air flow that pass through the counterflow part <NUM> flow in directions opposite to each other along the Y-axis direction. In each of the X-axis direction, the Y-axis direction, and the Z-axis direction, a side indicated by an arrow in the drawings is a positive side, and a side opposite the side indicated by the arrow is a negative side.

A plurality of first passage layers <NUM> included in the counterflow part <NUM> each include a sheet material <NUM> with a plurality of rib portions <NUM> formed thereon. Each of the rib portions <NUM> is a wall portion formed by bending the sheet material <NUM>. The rib portions <NUM> of each first passage layer <NUM> are arranged along the X-axis direction.

A plurality of second passage layers <NUM> included in the counterflow part <NUM> each include a sheet material <NUM> with a plurality of rib portions <NUM> formed thereon. Each of the rib portions <NUM> is a wall portion formed by bending the sheet material <NUM>. The rib portions <NUM> of each second passage layer <NUM> are arranged along the X-axis direction.

In the counterflow part <NUM>, spaces constituting the first passage and spaces constituting the second passage are formed by the rib portions <NUM> and <NUM>. In a ZX cross section of the counterflow part <NUM>, spaces constituting the first passage and spaces constituting the second passage are partitioned by the rib portions <NUM> and <NUM> into quadrangular shapes. The quadrangular shapes each have a larger length in the Z-axis direction than in the X-axis direction, and are trapezoids or rectangles. <FIG> illustrates an example in which the spaces constituting the first passage and the spaces constituting the second passage are each partitioned into trapezoids by the rib portions <NUM> and <NUM>.

The sheet materials <NUM> and <NUM> are thermally conductive sheet materials, and are metal sheets or resin sheets. The resin sheets may be moisture permeable resin sheets. The rib portions <NUM> and <NUM> are formed by bending the sheet materials <NUM> and <NUM> by processing such as stamping, compression molding, or vacuum molding.

Next, a structure of a first passage forming member <NUM> will be described. <FIG> is a perspective view of part of the first passage forming member illustrated in <FIG>. <FIG> is a perspective view of a rib portion in the structure illustrated in <FIG>. <FIG> is a perspective view of a rib portion and blocking portions in the structure illustrated in <FIG>.

<FIG>, <FIG>, and <FIG> each illustrate part of one rib portion <NUM> including an end <NUM> on the positive side in the Y-axis direction. The rib portion <NUM> has side wall portions <NUM>, <NUM>, and <NUM>, an upper face portion <NUM>, and a lower face portion <NUM>.

The side wall portions <NUM>, <NUM>, and <NUM> are thin-sheet wall portions installed to be raised in the X-axis direction, at intervals. In <FIG>, <FIG>, and <FIG>, the side wall portions <NUM>, <NUM>, and <NUM> installed to be raised in the Z-axis direction are illustrated. The individual side wall portions <NUM>, <NUM>, and <NUM> may be inclined with respect to the Z-axis direction.

The upper face portion <NUM> covers a space between two side wall portions <NUM> and <NUM> from the positive side in the Z-axis direction. The lower face portion <NUM> covers a space between two side wall portions <NUM> and <NUM> from the negative side in the Z-axis direction. Each of the upper face portion <NUM> and the lower face portion <NUM> illustrated in <FIG>, <FIG>, and <FIG> is a flat plate-like portion parallel to the X-axis direction and the Y-axis direction. Each of the upper face portion <NUM> and the lower face portion <NUM> is not limited to a flat shape, but may be curved.

The space surrounded by the lower face portion <NUM> and the side wall portions <NUM> and <NUM> serves as the first passage. The lower face portion <NUM> is a first wall portion that constitutes an end of the first passage on the negative side in the Z-axis direction. The space surrounded by the upper face portion <NUM> and the side wall portions <NUM> and <NUM> serves as the second passage. The upper face portion <NUM> is a second wall portion that constitutes an end of the second passage on the positive side in the Z-axis direction. The side wall portions <NUM>, <NUM>, and <NUM> are third wall portions that separates the first passage and the second passage that are adjacent in the X-axis direction from each other. Note that, when the side wall portions <NUM>, <NUM>, and <NUM> are installed to be raised in the Z-axis direction as illustrated in <FIG>, <FIG>, and <FIG>, the space constituting the first passage and the space constituting the second passage on the ZX cross section are each partitioned into a rectangular shape. When the side wall portions <NUM>, <NUM>, and <NUM> are inclined with respect to the Z-axis direction, the space constituting the first passage and the space constituting the second passage on the ZX cross section are each partitioned into a trapezoidal shape.

The board <NUM> is connected to the end <NUM> of the rib portion <NUM>. The board <NUM> is positioned at a center position of the length in the Z-axis direction of the rib portion <NUM>. The board <NUM> separates the inlet-side passage for the supply air flow from the outlet-side passage for the exhaust air flow. In other words, the inlet-side passage for the supply air flow, which is a first connection passage communicating with the first passage, and the outlet-side passage for the exhaust air flow, which is a second connection passage communicating with the second passage, are separated from each other by the board <NUM>. Among spaces on the positive side in the Y-axis direction with respect to the rib portion <NUM> illustrated in <FIG>, <FIG>, and <FIG>, a space on the positive side in the Z-axis direction with respect to the board <NUM> corresponds to the inlet-side passage for the supply air flow. Among the spaces on the positive side in the Y-axis direction with respect to the rib portion <NUM> illustrated in <FIG>, <FIG>, and <FIG>, a space on the negative side in the Z-axis direction with respect to the board <NUM> corresponds to the outlet-side passage for the exhaust air flow.

As illustrated in <FIG> and <FIG>, the first passage forming member <NUM> includes a first blocking portion <NUM> and a second blocking portion <NUM>, which are blocking portions installed at the end <NUM> of the rib portion <NUM>. The first blocking portion <NUM> blocks between the first passage that is surrounded by the lower face portion <NUM> and the side wall portions <NUM> and <NUM>, and the outlet-side passage for the exhaust air flow. The second blocking portion <NUM> blocks between the second passage surrounded by the upper face portion <NUM> and the side wall portions <NUM> and <NUM>, and the inlet-side passage for the supply air flow. In the first embodiment, the first blocking portion <NUM> and the second blocking portion <NUM> are each a flat plate parallel to the X-axis direction and to the Z-axis direction.

Part of the rib portion <NUM>, which includes an end on the negative side in the Y-axis direction of the rib portion <NUM>, has a structure similar to the part of the rib portion <NUM> that includes the end <NUM> on the positive side in the Y-axis direction of the rib portion <NUM> as illustrated in <FIG>, <FIG>, and <FIG>. The board <NUM> illustrated in <FIG> is connected to an end of the rib portion <NUM> on the negative side in the Y-axis direction. The board <NUM> is positioned at the center position of the length in the Z-axis direction of the rib portion <NUM> in a manner similar to the board <NUM>. The board <NUM> separates the outlet-side passage for the supply air flow from the inlet-side passage for the exhaust air flow. In other words, the outlet-side passage for the supply air flow, which is the first connection passage communicating with the first passage, and the inlet-side passage for the exhaust air flow, which is the second connection passage communicating with the second passage, are separated from each other by the board <NUM>. Among the spaces on the negative side in the Y-axis direction with respect to the rib portion <NUM>, a space on the positive side in the Z-axis direction with respect to the board <NUM> corresponds to the outlet-side passage for the supply air flow. Among the spaces on the positive side in the Y-axis direction with respect to the rib portion <NUM>, a space on the negative side in the Z-axis direction with respect to the board <NUM> corresponds to the inlet-side passage for the exhaust air flow.

A first blocking portion <NUM> and a second blocking portion <NUM> are installed at the end of the rib portion <NUM> on the negative side in the Y-axis direction in a manner similar to the end <NUM> of the rib portion <NUM>. The first blocking portion <NUM> blocks between the first passage and the inlet-side passage for the exhaust air flow. The second blocking portion <NUM> blocks between the second passage and the outlet-side passage for the supply air flow.

The second passage forming members <NUM> have a structure similar to that of the first passage forming members <NUM>. Each rib portion <NUM> has side wall portions <NUM>, <NUM>, and <NUM>, an upper face portion <NUM>, and a lower face portion <NUM> in a manner similar to the rib portion <NUM> illustrated in <FIG>, <FIG>, and <FIG>.

Part of the rib portion <NUM>, which includes an end on the positive side in the Y-axis direction of the rib portion <NUM> illustrated in <FIG>, has a structure similar to that of the part of the rib portion <NUM> that includes the end <NUM> on the positive side in the Y-axis direction of the rib portion <NUM>. The board <NUM> illustrated in <FIG> is connected to an end of the rib portion <NUM> on the positive side in the Y-axis direction. The board <NUM> is positioned at a center position of the length in the Z-axis direction of the rib portion <NUM>. The board <NUM> separates the outlet-side passage for the exhaust air flow from the inlet-side passage for the supply air flow. In other words, the inlet-side passage for the supply air flow, which is the first connection passage communicating with the first passage, and the outlet-side passage for the exhaust air flow, which is the second connection passage communicating with the second passage, are separated from each other by the board <NUM>. Among the spaces on the positive side in the Y-axis direction with respect to the rib portion <NUM>, a space on the positive side in the Z-axis direction with respect to the board <NUM> corresponds to the outlet-side passage for the exhaust air flow. Among the spaces on the positive side in the Y-axis direction with respect to the rib portion <NUM>, a space on the negative side in the Z-axis direction with respect to the board <NUM> corresponds to the inlet-side passage for the supply air flow.

A first blocking portion <NUM> and a second blocking portion <NUM> are installed at the end of the rib portion <NUM> on the positive side in the Y-axis direction in a manner similar to the end <NUM> of the rib portion <NUM>. The first blocking portion <NUM> blocks between the first passage and the outlet-side passage for the exhaust air flow. The second blocking portion <NUM> blocks between the second passage and the inlet-side passage for the supply air flow.

Part of the rib portion <NUM>, which includes an end on the negative side in the Y-axis direction of the rib portion <NUM>, has a structure similar to the part of the rib portion <NUM> including the end <NUM> on the positive side in the Y-axis direction of the rib portion <NUM> as illustrated in <FIG>, <FIG>, and <FIG>. The board <NUM> illustrated in <FIG> is connected to an end of the rib portion <NUM> on the negative side in the Y-axis direction. The board <NUM> is positioned at a center position of the length in the Z-axis direction of the rib portion <NUM>. The board <NUM> separates the inlet-side passage for the exhaust air flow from the outlet-side passage for the supply air flow. In other words, the outlet-side passage for the supply air flow, which is the first connection passage communicating with the first passage, and the inlet-side passage for the exhaust air flow, which is the second connection passage communicating with the second passage, are separated from each other by the board <NUM>. Among the spaces on the negative side in the Y-axis direction with respect to the rib portion <NUM>, a space on the positive side in the Z-axis direction with respect to the board <NUM> corresponds to the inlet-side passage for the exhaust air flow. Among the spaces on the negative side in the Y-axis direction with respect to the rib portion <NUM>, a space on the negative side in the Z-axis direction with respect to the board <NUM> corresponds to the outlet-side passage for the supply air flow.

Next, the first passage and the second passage included in the counterflow part <NUM> will be described. <FIG> is a perspective view of the first passages and the second passages included in the counterflow part of the heat exchanging element according to the first embodiment. <FIG> is a plane view of the first passages and the second passages illustrated in <FIG> and boards.

<FIG> schematically illustrates a first passage layer <NUM> including rib portions <NUM>, first blocking portions <NUM> and second blocking portions <NUM>, and a second passage layer <NUM> including rib portions <NUM>, first blocking portions <NUM>, and second blocking portions <NUM>. <FIG> illustrates an end of the first passage layer <NUM> on the positive side in the Y-axis direction, and an end of the second passage layer <NUM> on the positive side in the Y-axis direction. <FIG> illustrates a structure of the counterflow part <NUM> at the end on the positive side in the Y-axis direction. In <FIG> and <FIG>, the boundaries between the rib portions <NUM> and the first blocking portions <NUM>, the boundaries between the rib portions <NUM> and the second blocking portions <NUM>, the boundaries between the rib portions <NUM> and the first blocking portions <NUM>, and the boundaries between the rib portions <NUM> and the second blocking portions <NUM> are not illustrated. Furthermore, although the first passage layer <NUM> and the second passage layer <NUM> are illustrated as being separated from each other in <FIG>, a first passage layer <NUM> and a second passage layer <NUM> adjacent to each other in the Z-axis direction are connected with each other.

In the structure illustrated in <FIG>, a first passage <NUM> is formed on the positive side in the Z-axis direction with respect to the board <NUM> in the first passage layer <NUM>. At an end of the first passage layer <NUM> on the positive side in the Y-axis direction, an area that is adjacent in the X-axis direction to the first passage <NUM> is blocked by a second blocking portion <NUM>. A second passage <NUM> is formed on the negative side in the Z-axis direction with respect to the board <NUM> in the first passage layer <NUM>. At the end of the first passage layer <NUM> on the positive side in the Y-axis direction, an area that is adjacent in the X-axis direction to the second passage <NUM> is blocked by a first blocking portion <NUM>. About half the area at the end of the first passage layer <NUM> on the positive side in the Y-axis direction, is blocked by the first blocking portion <NUM> or the second blocking portion <NUM>.

In addition, in the structure illustrated in <FIG>, the second passage <NUM> is formed on the positive side in the Z-axis direction with respect to the board <NUM> in the second passage layer <NUM>. At the end of the second passage layer <NUM> on the positive side in the Y-axis direction, an area that is adjacent in the X-axis direction to the second passage <NUM> is blocked by a first blocking portion <NUM>. The first passage <NUM> is formed on the negative side in the Z-axis direction with respect to the board <NUM> in the second passage layer <NUM>. At the end of the second passage layer <NUM> on the positive side in the Y-axis direction, an area that is adjacent in the X-axis direction to the first passage <NUM> is blocked by a second blocking portion <NUM>. About half the area at the end of the second passage layer <NUM> on the positive side in the Y-axis direction, is blocked by the first blocking portion <NUM> or the second blocking portion <NUM>.

<FIG> illustrates a cross section of a center part in the Y-axis direction of the first passage layer and the second passage layer that form the first passages and the second passages illustrated in <FIG> and <FIG>. In the first passage layer <NUM>, the first passages <NUM> and the second passages <NUM> are separated from each other by the side wall portions <NUM>, <NUM>, and <NUM> of the rib portions <NUM>. In the second passage layer <NUM>, the first passages <NUM> and the second passages <NUM> are separated from each other by the side wall portions <NUM>, <NUM>, and <NUM> of the rib portions <NUM>. Each of the first passages <NUM> in the first passage layer <NUM> and each of the second passages <NUM> in the second passage layer <NUM> are separated from each other by the lower face portions <NUM>. Each of the second passages <NUM> in the first passage layer <NUM> and each of the first passages <NUM> in the second passage layer <NUM> are separated from each other by the upper face portions <NUM>.

<FIG> is a first diagram for explaining a state in which a supply air flow and an exhaust air flow pass through the heat exchanging element according to the first embodiment. <FIG> is a second diagram for explaining a state in which the supply air flow and the exhaust air flow pass through the heat exchanging element according to the first embodiment. <FIG> is a third diagram for explaining a state in which the supply air flow and the exhaust air flow pass through the heat exchanging element according to the first embodiment.

<FIG> illustrates a state in which a supply air flow <NUM> and an exhaust air flow <NUM> pass through passages on the positive side in the Y-axis direction with respect to the first passage layer <NUM> and the second passage layer <NUM>. <FIG> illustrates a state in which the supply air flow <NUM> and the exhaust air flow <NUM> pass an end of the first passage layer <NUM> on the positive side in the Y-axis direction. <FIG> illustrates a state in which the supply air flow <NUM> and the exhaust air flow <NUM> pass in each of the first passage layer <NUM> and the second passage layer <NUM>. Note that, in <FIG>, <FIG>, and <FIG>, broken lines schematically expressing boundaries between the first passages <NUM> and the second passages <NUM> in the cross section illustrated in <FIG> are illustrated.

<FIG> illustrates two first passage layers <NUM> and one second passage layer <NUM> placed between the two first passage layers <NUM>. In addition, a ZX plane illustrated in <FIG> is divided into six regions in the Z-axis direction and into six regions in the X-axis direction, and each divisional region is represented by a combination of a number indicating a position in the Z-axis direction and a number indicating a position in the X-axis direction. For example, (<NUM>,<NUM>) represents a divisional region at Z=<NUM> and X=<NUM>. Z=<NUM> indicates a second divisional region from the positive side in the Z-axis direction in <FIG>. X=<NUM> indicates a first divisional region from the negative side in the X-axis direction in <FIG>. <FIG> and <FIG> also illustrate two first passage layers <NUM>, one second passage layer <NUM>, and divisional regions in a manner similar to <FIG>.

In <FIG>, the supply air flow <NUM> flows through an inlet-side passage <NUM> across six divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>). In addition, the supply air flow <NUM> flows through an inlet-side passage <NUM> across twelve divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>).

In <FIG>, the exhaust air flow <NUM> flows through an outlet-side passage <NUM> across twelve divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>). In addition, the exhaust air flow <NUM> flow through an outlet-side passage <NUM> across six divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>).

In <FIG>, three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>) among six divisional regions located at Z=<NUM> are blocked by second blocking portions <NUM>. The supply air flow <NUM> having passed through the inlet-side passage <NUM> across six divisional regions at Z=<NUM> passes through any one of three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>), and flows to the first passage <NUM>.

In <FIG>, three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>) among six divisional regions located at Z=<NUM> are blocked by first blocking portions <NUM>. In <FIG>, three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>) among six divisional regions located at Z=<NUM> are blocked by first blocking portions <NUM>. The exhaust air flow <NUM> having passed through the second passages <NUM> located at Z=<NUM>, <NUM> passes through any one of six divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>), and flows to the outlet-side passage <NUM> across twelve divisional regions located at Z=<NUM>, <NUM>.

In <FIG>, three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>) among six divisional regions located at Z=<NUM> are blocked by second blocking portions <NUM>. In <FIG>, three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>) among six divisional regions located at Z=<NUM> are blocked by second blocking portions <NUM>. The supply air flow <NUM> having passed through the inlet-side passage <NUM> across twelve divisional regions located at Z=<NUM>, <NUM> passes through any one of six divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>), and flows to the first passage <NUM>.

In <FIG>, three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>) among six divisional regions located at Z=<NUM> are blocked by first blocking portions <NUM>. The exhaust air flow <NUM> having passed through the second passages <NUM> located at Z=<NUM> passes through any one of three divisional regions (<NUM>,<NUM>), (<NUM>,<NUM>), and (<NUM>,<NUM>), and flows to the outlet-side passage <NUM> across six divisional regions located at Z=<NUM>.

The supply air flow <NUM> having passed through the divisional region (<NUM>,<NUM>) in <FIG> flows through the first passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG>. The supply air flow <NUM> having passed through the divisional region (<NUM>,<NUM>) in <FIG> flows through the first passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG>. The supply air flow <NUM> having passed through the divisional region (<NUM>,<NUM>) in <FIG> flows through the first passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG>.

The exhaust air flow <NUM> having passed through the second passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG> is gathered in the divisional region (<NUM>,<NUM>) in <FIG> and then flows to the outlet-side passage <NUM>. The exhaust air flow <NUM> having passed through the second passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG> is gathered in the divisional region (<NUM>,<NUM>) in <FIG> and then flows to the outlet-side passage <NUM>. The exhaust air flow <NUM> having passed through the second passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG> is gathered in the divisional region (<NUM>,<NUM>) in <FIG> and then flows to the outlet-side passage <NUM>.

The exhaust air flow <NUM> having passed through the second passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG> is gathered in the divisional region (<NUM>,<NUM>) in <FIG> and then flows toward the outlet-side passage <NUM>. The exhaust air flow <NUM> having passed through the second passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG> is gathered in the divisional region (<NUM>,<NUM>) in <FIG> and then flows toward the outlet-side passage <NUM>. The exhaust air flow <NUM> having passed through the second passage <NUM> across two divisional regions (<NUM>,<NUM>) and (<NUM>,<NUM>) in <FIG> is gathered in the divisional region (<NUM>,<NUM>) in <FIG> and then flows toward the outlet-side passage <NUM>.

As illustrated in <FIG>, the first passage <NUM> and the second passage <NUM> adjacent to each other in the X-axis direction are formed in the first passage layer <NUM> and the second passage layer <NUM>. Because the first passage <NUM> and the second passage <NUM> are adjacent to each other in the X-axis direction, the heat exchanging element <NUM> can improve the heat exchange efficiency between the supply air flow <NUM> and the exhaust air flow <NUM>.

The rib portions <NUM> and <NUM> forming the first passage <NUM> and the second passage <NUM> are made of combination of thin sheet-like parts, and can be produced by bending the sheet materials <NUM> and <NUM> by processing such as compression molding. In this manner, the counterflow part <NUM> including the rib portions <NUM> and <NUM> can be easily produced.

According to the first embodiment, the heat exchanging element <NUM> includes the rib portions <NUM> and <NUM> forming the counterflow part <NUM>, the boards <NUM>, <NUM>, <NUM>, and <NUM> in contact with the ends of the rib portions <NUM> and <NUM>, the first blocking portions <NUM>, and the second blocking portions <NUM>. Because the counterflow part <NUM> is configured by the rib portions <NUM> and <NUM>, the first passage <NUM> and the second passage <NUM> arranged alternately in the X-axis direction can be formed in the counterflow part <NUM>. As a result, the heat exchanging element <NUM> produces an effect of enabling improvement in the heat exchange efficiency.

<FIG> illustrates a cross section of a rib portion included in a heat exchanging element according to a second embodiment. In the second embodiment, the thicknesses of the side wall portions <NUM>, <NUM>, and <NUM> forming the rib portions <NUM> and <NUM> are set so that the efficiency of heat exchange between the supply air flow <NUM> and the exhaust air flow <NUM> can be improved. In the second embodiment, components that are the same as those in the first embodiment described above will be represented by the same reference numerals, and features different from those in the first embodiment will be mainly described.

<FIG> illustrates part of one rib portion <NUM> including an end thereof on the positive side in the Y-axis direction. The side wall portions <NUM>, <NUM>, and <NUM> have thicknesses smaller than that of the upper face portions <NUM> and smaller than that of the lower face portions <NUM>. The rib portions <NUM> have a structure similar to that of the rib portions <NUM>. In the second embodiment, assume that the rib portions <NUM> and <NUM> are produced by compression molding.

Because the side wall portions <NUM>, <NUM>, and <NUM> are thinner than the upper face portions <NUM> and the lower face portions <NUM>, the heat exchanging element <NUM> can improve the efficiency of heat exchange between the supply air flow <NUM> in the first passage <NUM> and the exhaust air flow <NUM> in the second passage <NUM>, which are separated from each other by the side wall portions <NUM>, <NUM>, and <NUM>. As a result, the heat exchanging element <NUM> can improve the heat exchange efficiency. In addition, because the upper face portions <NUM> and the lower face portions <NUM> are thicker than the side wall portions <NUM>, <NUM>, and <NUM>, the heat exchanging element <NUM> can have a high stiffness.

The side wall portions <NUM>, <NUM>, and <NUM> forming the rib portions <NUM> and <NUM>, the upper face portions <NUM>, and the lower face portions <NUM> each have a thickness smaller than that of outer edges of the sheet materials <NUM> and <NUM>. In the second embodiment, the thicknesses of the side wall portions <NUM>, <NUM>, and <NUM>, the thickness of the upper face portions <NUM>, and the thickness of the lower face portions <NUM> are within a range from <NUM>% to <NUM>% of the thickness of the outer edges of the sheet materials <NUM> and <NUM>. The side wall portions <NUM>, <NUM>, and <NUM>, the upper face portions <NUM>, and the lower face portion <NUM> that are thinner than the outer edges of the sheet materials <NUM> and <NUM> can be easily formed by processing the sheet materials <NUM> and <NUM> by compression molding.

In addition, it is preferable that the thicknesses of the side wall portions <NUM>, <NUM>, and <NUM> fall within a range from <NUM>% to <NUM>% of the thicknesses of the outer edges of the sheet materials <NUM> and <NUM>. The lengths of the side wall portions <NUM>, <NUM>, and <NUM> in the directions in which the side wall portions <NUM>, <NUM>, and <NUM> are installed to be raised from the lower face portions <NUM> are preferably longer than the length of the upper face portions <NUM> in the X-axis direction and longer than the length of the lower face portions <NUM> in the X-axis direction. As a result, the heat exchanging element <NUM> can improve the efficiency of heat exchange between the supply air flow <NUM> in the first passage <NUM> and the exhaust air flow <NUM> in the second passage <NUM>. In addition, when the thicknesses of the side wall portions <NUM>, <NUM>, and <NUM> are smaller than half of the thicknesses of the outer edges of the sheet materials <NUM> and <NUM>, the rib portions <NUM> and <NUM> are easily produced by compression molding.

It is preferable that the thickness of the upper face portions <NUM> and the thickness of the lower face portions <NUM> fall within a range from <NUM>% to <NUM>% of the thicknesses of the outer edges of the sheet materials <NUM> and <NUM>. The upper face portions <NUM> and the lower face portions <NUM> have a function of maintaining the strength of the rib portions <NUM> and <NUM> as a whole. Thus, the thickness of the upper face portions <NUM> and the thickness of the lower face portions <NUM> are preferably twice the thicknesses of the side wall portions <NUM>, <NUM>, and <NUM> or larger.

Furthermore, it is preferable that the thickness of the lower face portions <NUM> falls within a range from <NUM>% to <NUM>% of the thicknesses of the outer edges of the sheet materials <NUM> and <NUM>. It is preferable that the thickness of the upper face portions <NUM> falls within a range from <NUM> to <NUM>% of the thicknesses of the outer edges of the sheet materials <NUM> and <NUM>. In the heat exchanging element <NUM>, the thickness of the lower face portions <NUM> may be within a range from <NUM>% to <NUM>% of the thicknesses of the outer edges of the sheet materials <NUM> and <NUM>, and the thickness of the upper face portions <NUM> may be within a range from <NUM>% to <NUM>% of the thicknesses of the outer edges of the sheet materials <NUM> and <NUM>. As a result, the rib portions <NUM> and <NUM> as a whole can have a high strength in the heat exchanging element <NUM>.

<FIG> is a schematic cross-sectional view of a sheet material included in the heat exchanging element according to the second embodiment. <FIG> schematically illustrates a cross section of the sheet material <NUM>. "t1" represents the thickness of an outer edge of the sheet material <NUM>. The outer edge is a portion, which is not processed by compression molding, of the sheet material <NUM>. Before machining for producing rib portions <NUM> is performed, the thickness of the entire sheet material <NUM> is t1. "t2" represents the thickness of a lower face portion <NUM>. "t3" represents the thickness of an upper face portion <NUM>. "t4" represents the thickness of a side wall portion <NUM>. The thickness of each of the side wall portion <NUM> and the side wall portion <NUM> is also t4. "W" represents the width in the X-axis direction of part of the rib portion <NUM> including two side wall portions <NUM> and <NUM> and the lower face portion <NUM>. "W" corresponds to the pitch of the side wall portions <NUM>, <NUM>, and <NUM>. "H" represents the length in the Z-axis direction of the rib portion <NUM>, which is the length from the upper face portion <NUM> to the lower face portion <NUM>.

Because the respective portions of the rib portion <NUM> are subjected to compression molding, t2, t3, and t4 are all smaller than t1. In addition, in the second embodiment, t1 is <NUM>, t2 is between <NUM> and <NUM>, and t3 is between <NUM> and <NUM>. When the rib portion <NUM> has an aspect ratio W:H of <NUM>:<NUM>, t4 is <NUM>. When W:H is <NUM>:<NUM>, t4 is <NUM>. When W:H is <NUM>:<NUM>, t4 is <NUM>. When W:H is <NUM>:<NUM>, t4 is <NUM>. W is between <NUM> and <NUM>. W is most preferably <NUM>. It is preferable that the thicknesses of the sheet material <NUM> and the respective portions of the rib portion <NUM> satisfy t1>t2>t3>t4.

As t4 is smaller, the heat exchanging element <NUM> can make the efficiency of heat exchange between the supply air flow <NUM> and the exhaust air flow <NUM> higher. When t4 is too small, however, the side wall portions <NUM>, <NUM>, and <NUM> become more likely to be damaged. Accordingly, a lower limit of t4 is preferably about <NUM>.

Because the rib portions <NUM> and <NUM> are stacked, a load in the Z-axis direction is applied to each rib portion <NUM>. The load in a state in which both ends of the rib portion <NUM> in the X-axis direction are supported, becomes a factor of deflection of the rib portion <NUM> at the center of its length in the X-axis direction. Because, however, the rib portion <NUM> is reinforced by the boards <NUM> and <NUM>, the first blocking portion <NUM>, and the second blocking portion <NUM>, deformation of the rib portion <NUM> by the deflection of the rib portion <NUM> at the center of its length in the X-axis direction can be reduced.

The load in a state in which both ends of the rib portion <NUM> in the Y-axis direction are supported is a factor of deflection of the rib portion <NUM> at the center of its length in the Y-axis direction. The strength of the rib portion <NUM> against the deflection is determined by t2, t3, and t4. Because t4 is preferably as small as possible as described above, the functions of the side wall portions <NUM>, <NUM>, and <NUM> as a function of reinforcing members against the deflection are small. Thus, the strength of the rib portion <NUM> against the deflection is determined by t2 and t3.

Because the rib portion <NUM> is formed by compression molding, an average of t2 and t3 is generally constant. Specifically, as t2 is larger, t3 is smaller. When the average of t2 and t3 is constant, the strength of the rib portion <NUM> is higher when t2 and t3 are different from each other than when t2 and t3 are equal to each other. For example, the strength of the rib portion <NUM> is higher when t2=<NUM> and t3=<NUM> than when t2=t3=<NUM>. Thus, the rib portion <NUM> preferably satisfies t2>t3. Furthermore, the rib portion <NUM> preferably satisfies t2≈<NUM>×t3.

For example, heat exchange of air flowing through a passage illustrated as a region of H×W in the ZX cross section in <FIG> is carried out via the side wall portions <NUM>, <NUM>, and <NUM>, which are portions having the length H of the rib portion <NUM>. In order to facilitate the heat exchange, the rib portion <NUM> preferably satisfy H>W. In addition, H is preferably twice the width W or larger. At the rib portion <NUM>, heat exchange is carried out by counterflow between one face side and the other face side of the side wall portions <NUM>, <NUM>, and <NUM>. When H is made twice the width W or larger, the ratio of the length of a part at which heat exchange is carried out to the cross-sectional area of a passage is increased, which allows the heat exchanging element <NUM> to improve the heat exchange efficiency.

Note that the side wall portions <NUM>, <NUM>, and <NUM> may be raised in the Z-axis direction, or may be inclined with respect to the Z-axis direction as illustrated in <FIG>. In a state in which the side wall portions <NUM>, <NUM>, and <NUM> are inclined with respect to the Z-axis direction, the side wall portions <NUM>, <NUM>, and <NUM> and the upper face portion <NUM> are connected with each other at obtuse angles, and the side wall portions <NUM>, <NUM>, and <NUM> and the lower face portion <NUM> are connected with each other at obtuse angles. When the side wall portions <NUM>, <NUM>, and <NUM> are inclined so that the angles between the side wall portions <NUM>, <NUM>, and <NUM> and the upper face portion <NUM> and the angles between the side wall portions <NUM>, <NUM>, and <NUM> and the lower face portion <NUM> are obtuse angles, an effect of facilitating formation of the rib portion <NUM> is produced. In this case, the inclination angles of the side wall portions <NUM>, <NUM>, and <NUM> with respect to the Z-axis direction, which is the stacking direction, are preferably equal to or smaller than <NUM> degrees. When the inclination angles are equal to or smaller than <NUM> degrees, the ratio of the length of a part at which heat exchange is carried out to the cross-sectional area of a passage is increased, which enables the heat exchanging element <NUM> to improve the heat exchange efficiency.

In addition, the rib portion <NUM> preferably satisfies t3>t4. t3 is preferably within a range from <NUM>×t4 to <NUM>×t4, and more preferably satisfies t3≈<NUM>×t4. As a result, the heat exchanging element <NUM> can maintain the strength of the side wall portions <NUM>, <NUM>, and <NUM> and improve the heat exchange efficiency.

In a third embodiment, an example of a heat exchanging element having a structure similar to that of the heat exchanging element in the first or second embodiment will be described. <FIG> is a perspective view of an overall structure of a heat exchanging element according to the third embodiment. In the third embodiment, components that are the same as those in the first or second embodiment described above will be represented by the same reference numerals, and features different from those in the first or second embodiment will be mainly described.

A heat exchanging element <NUM> according to the third embodiment is a counterflow heat exchanging element. The heat exchanging element <NUM> is a layered structure including first passage forming members <NUM> and second passage forming members <NUM> that are alternately stacked. The number of first passage forming members <NUM> included in the heat exchanging element <NUM> and the number of second passage forming members <NUM> included in the heat exchanging element <NUM> each may be any numbers.

The heat exchanging element <NUM> includes a counterflow part <NUM> in which heat exchange between a supply air flow and an exhaust air flow is carried out, a first separated passage part <NUM>, and a second separated passage part <NUM>. The counterflow part <NUM> has a structure similar to the counterflow part <NUM> in the first or second embodiment. The counterflow part <NUM> includes a first passage, and a second passage through which an exhaust air flow <NUM> flows in a direction opposite to a supply air flow <NUM> flowing through the first passage. Thus, in the counterflow part <NUM>, the flowing direction of the supply air flow <NUM> and the flowing direction of the exhaust air flow <NUM> are different from each other by <NUM> degrees. The counterflow part <NUM> has a rectangular parallelepiped shape.

The heat exchanging element <NUM> exchanges sensible heat between the supply air flow <NUM> and the exhaust air flow <NUM> by heat transfer between the first passage and the second passage. The heat exchanging element <NUM> exchanges latent heat between the supply air flow <NUM> and the exhaust air flow <NUM> by circulation of water vapor between the first passage and the second passage.

The first separated passage part <NUM> is connected to an end of the counterflow part <NUM> on the upstream side of the supply air flow <NUM> and the downstream side of the exhaust air flow <NUM>. The second separated passage part <NUM> is connected to an end of the counterflow part <NUM> on the downstream side of the supply air flow <NUM> and the upstream side of the exhaust air flow <NUM>. The first separated passage part <NUM> and the second separated passage part <NUM> each have a triangular prism shape.

An inlet-side passage <NUM> for the supply air flow <NUM> and an outlet-side passage <NUM> for the exhaust air flow <NUM> are formed in the first separated passage part <NUM>. The first separated passage part <NUM> includes partitions <NUM> and spacing ribs <NUM>. The partition <NUM> is a component corresponding to the board <NUM> illustrated in <FIG> or the board <NUM> illustrated in <FIG>. The partitions <NUM> separate the inlet-side passage <NUM> and the outlet-side passage <NUM> from each other.

The spacing ribs <NUM> have a quadrangular cross section. In one example, the spacing ribs <NUM> are formed by molding a resin material. Among the spacing ribs <NUM>, spacing ribs 67A installed on the first passage forming member <NUM> partition the inlet-side passage <NUM>. The spacing rib 67A is a component corresponding to the passage wall <NUM> illustrated in <FIG>. Among the spacing ribs <NUM>, spacing ribs 67B installed on the second passage forming member <NUM> partition the outlet-side passage <NUM>. The spacing rib 67B is a component corresponding to the passage wall <NUM> illustrated in <FIG>.

An outlet-side passage for the supply air flow <NUM> and an inlet-side passage for the exhaust air flow <NUM> are formed in the second separated passage part <NUM>. The second separated passage part <NUM> has a structure similar to that of the first separated passage part <NUM>. The structure of the second separated passage part <NUM> is not illustrated.

In the first separated passage part <NUM>, an end on the upstream side of the inlet-side passage <NUM> for the supply air flow <NUM> and an end on the downstream side of the outlet-side passage <NUM> for the exhaust air flow <NUM> face toward different directions from each other. In the second separated passage part <NUM>, an end on the downstream side of the outlet-side passage for the supply air flow <NUM> and an end on the upstream side of the inlet-side passage for the exhaust air flow <NUM> face toward different directions from each other.

In the third embodiment, the counterflow part <NUM> includes the rib portions <NUM> and <NUM>, the first blocking portions <NUM>, and the second blocking portions <NUM> in a manner similar to the counterflow part <NUM> in the first or second embodiment. The heat exchanging element <NUM> can improve the heat exchange efficiency in a manner similar to the heat exchanging element <NUM> of the first or second embodiment.

In a fourth embodiment, a heat exchange ventilator including the heat exchanging element <NUM> according to the first or second embodiment will be described. <FIG> is a diagram illustrating a schematic configuration of the heat exchange ventilator according to the fourth embodiment. The heat exchange ventilator <NUM> according to the fourth embodiment includes the heat exchanging element <NUM> according to the first or second embodiment. The heat exchange ventilator <NUM> ventilates the inside of a room by drawing a supply air flow <NUM> from the outside into the inside of the room, and discharging an exhaust air flow <NUM> from the inside to the outside of the room. In addition, the heat exchange ventilator <NUM> allows heat exchange between the supply air flow <NUM> and the exhaust air flow <NUM> in the heat exchanging element <NUM>.

In a casing <NUM> of the heat exchange ventilator <NUM>, a supply air passage <NUM> through which the supply air flow <NUM> passes and an exhaust air passage <NUM> through which the exhaust air flow <NUM> passes are formed. A supply fan <NUM> for generating the supply air flow <NUM> is arranged on the supply air passage <NUM>. An exhaust fan <NUM> for generating the exhaust air flow <NUM> is installed on the exhaust air passage <NUM>. <FIG> schematically illustrates components set in the casing <NUM>.

A supply air outlet port <NUM> and an exhaust air inlet port <NUM> are provided on a side face on the indoor side of the casing <NUM>. A supply air inlet port <NUM> and an exhaust air outlet port <NUM> are provided on a side face on the outdoor side of the casing <NUM>. The heat exchange ventilator <NUM> operates the supply fan <NUM> to draw air from the outside into the supply air passage <NUM> via the supply air inlet port <NUM> to generate the supply air flow <NUM>. The supply air flow <NUM> passes through the supply air passage <NUM> and is sent out toward the inside of the room via the supply air outlet port <NUM>. In addition, the heat exchange ventilator <NUM> operates the exhaust fan <NUM> to draw air from the inside of the room into the exhaust air passage <NUM> via the exhaust air inlet port <NUM> to generate the exhaust air flow <NUM>. The exhaust air flow <NUM> passes through the exhaust air passage <NUM> and is sent out toward the outside via the exhaust air outlet port <NUM>.

The heat exchanging element <NUM> is located at a position at which the supply air passage <NUM> and the exhaust air passage <NUM> intersect. In the heat exchanging element <NUM>, total heat exchange between the supply air flow <NUM> and the exhaust air flow <NUM> is carried out. The heat exchange ventilator <NUM> recovers sensible heat and latent heat of the exhaust air flow <NUM> from inside the room by total heat exchange in the heat exchanging element <NUM>, and transfers the recovered sensible heat and latent heat to the supply air flow <NUM>. In addition, the heat exchange ventilator <NUM> recovers sensible heat and latent heat of the supply air flow <NUM> from the outside, and transfers the recovered sensible heat and latent heat to the exhaust air flow <NUM>. The heat exchange ventilator <NUM> can improve the efficiency of heating and cooling and the efficiency of humidification and dehumidification of the inside of a room, and reduce energy used for air conditioning of the inside of the room. Alternatively, the heat exchange ventilator <NUM> may include the heat exchanging element <NUM> according to the third embodiment instead of the heat exchanging element <NUM> according to the first or second embodiment.

The heat exchange ventilator <NUM> according to the fourth embodiment includes the heat exchanging element <NUM> according to the first or second embodiment or the heat exchanging element <NUM> according to the third embodiment, which can improve the heat exchange efficiency.

Claim 1:
A heat exchanging element (<NUM>; <NUM>) comprising a first passage forming member (<NUM>) and a second passage forming member (<NUM>) stacked alternately, the heat exchanging element including a counterflow part (<NUM>; <NUM>) that includes a first passage (<NUM>) through which air passes and a second passage (<NUM>) through which air flows in a direction opposite a direction in which the air passes through the first passage (<NUM>), wherein
the first passage forming member (<NUM>) and the second passage forming member (<NUM>) each include:
a rib portion (<NUM>), which constitutes the counterflow part (<NUM>; <NUM>), including a first wall portion (<NUM>) constituting an end in a first direction of the first passage (<NUM>), a second wall portion (<NUM>) constituting an end in the first direction of the second passage (<NUM>), and a third wall portion (<NUM>, <NUM>, <NUM>) separating the first passage (<NUM>) and the second passage (<NUM>) adjacent to each other in a second direction from each other, the first direction being a direction in which the first passage forming member (<NUM>) and the second passage forming member (<NUM>) are stacked, the second direction being perpendicular to the first direction;
the heat exchanging element (<NUM>; <NUM>) being characterized by a board (<NUM>) being in contact with an end (<NUM>) in a third direction of the rib portion, and separating a first connection passage communicating with the first passage (<NUM>) and a second connection passage communicating with the second passage (<NUM>) from each other, the third direction being perpendicular to the first direction and to the second direction;
a first blocking portion (<NUM>) installed at the end (<NUM>) of the rib portion (<NUM>), to block between the first passage (<NUM>) and the second connection passage; and
a second blocking portion (<NUM>) installed at the end (<NUM>) of the rib portion (<NUM>), to block between the second passage (<NUM>) and the first connection passage.