WO2005036067A1

WO2005036067A1 - Ventilator

Info

Publication number: WO2005036067A1
Application number: PCT/KR2003/002129
Authority: WO
Inventors: Min-Chul Cho; Seonghwan Lee; Soo-Yeon Shin
Original assignee: Lg Electronics, Inc.
Priority date: 2003-10-14
Filing date: 2003-10-14
Publication date: 2005-04-21
Also published as: EP1680627A1; AU2003271208A1

Abstract

The present invention discloses a ventilator (50) for exchanging heat between indoor air and outdoor air, and ventilating an indoor space by externally discharging indoor air (54) and internally sucking outdoor air (56). In the ventilator, suction directions of outdoor air or indoor air are inclined to the length direction of a heat exchanger (60) for exchanging heat. Accordingly, the ventilator reduces flow resistances due to rapid variations of suction flow directions of air, and thus improves air flow efficiency and heat exchange efficiency. In addition, the ventilator is firmly coupled to indoor or outdoor ducts by changing a shape of a casing for smoothly forming the suction flow directions of air. Furthermore, the ventilator is miniaturized by reducing an unnecessary space of the casing.

Description

VENTILATOR

TECHNICAL FIELD The present invention relates to a ventilator for ventilating an indoor space by externally discharging indoor air and internally sucking outdoor air.

BACKGROUND ART In general, the carbon dioxide content of a ir increases in a h ermetically sealed space with the passage of time because of breathing of living objects, and has detrimental effects on breathing. Accordingly, a ventilator is used to exchange contaminated indoor air for fresh outdoor air especially in a narrow space where a number of people stay such as an office or vehicle. The ventilator includes an air blower for forcibly blowing indoor air and • outdoor air, and repeats a process of externally discharging contaminated indoor air and internally sucking fresh outdoor air. However, when cooling and ventilating operations are performed indoors at the same time, cooled indoor air is exhausted and hot outdoor air is sucked. Thus, a temperature of indoor air is higher than a cooling temperature, to reduce cooling efficiency. In the case that heating and ventilating operations are simultaneously performed indoors, heated indoor air is exhausted and cooled outdoor air is sucked. As a result, the temperature of indoor air is lower than a heating temperature, to reduce heating efficiency. Therefore, the ventilator further includes a heat exchanger for exchanging heat between indoor air and outdoor air. In detail, in a ventilator disclosed in Japanese Laid-Open Patent Application 11-287492, as shown in Fig. 1 , an outdoor air suction hole 4a for sucking outdoor air and an indoor air discharge hole 6b for discharging indoor air are formed on one surface of a rectangular casing 2, and an outdoor air discharge hole 4b for discharging outdoor air and an indoor air suction hole 6a for sucking indoor air are formed on the other surface of the casing 2. Here, the outdoor air suction hole 4a and the indoor air discharge hole 6b are formed in one side and the other side of one side surface of the casing 2, and the outdoor air discharge hole 4b and the indoor air suction hole 6a are formed in one side and the other side of the other side surface of the casing 2. Ducts (not shown) linked to the outdoor side are vertically connected to the outdoor air suction hole 4a and the indoor air discharge hole 6b, and ducts (not shown) linked to the indoor side are vertically connected to the outdoor air discharge hole 4b and the indoor air suction hole 6a. A heat exchanger 8 for forming passages for separately flowing indoor air •and outdoor air, and exchanging heat is installed to cross the center of the casing 2, and an air supply fan 10 and an air exhaust fan 20 are installed in both edges of the casing 2 to be positioned inside the outdoor air discharge hole 4b and the indoor air discharge hole 6b. The heat exchanger 8 is installed to be freely connected or disconnected through a checking hole 2a formed in the center of one surface of the casing 2. An outdoor air passage guide 32 for forming an air path for guiding outdoor air sucked from the o utdoor a ir suction hole 4 a to the h eat exchanger 8 to b e discharged to the outdoor air discharge hole 4b is installed in one side of the casing 2 from the heat exchanger 8, and an indoor air passage guide 34 for forming an air path for guiding indoor air sucked from the indoor air suction hole 6a to the heat exchanger 8 to be discharged to the indoor air discharge hole 6b is installed in the other side of the casing 2 from the heat exchanger 8. The operation of the ventilator will now be explained with reference to Fig. 2. When the air supply fan 10 and the air exhaust fan 20 are operated, outdoor air sucked from the outdoor air suction hole 4a is guided by the outdoor air passage guide 32 and sucked to the bottom of one side of the heat exchanger 8, and indoor air sucked from the indoor air suction hole 6a is guided by the indoor air passage guide 34 a nd s ucked to the b ottom of t he o ther side o f t he h eat e xchanger 8. Outdoor air and indoor air exchange heat through the heat exchanger 8. Thereafter, outdoor air passing through the heat exchanger 8 is guided by the duct through the air supply fan 10 and the outdoor air discharge hole 4b and sucked to the indoor side, and indoor air passing through the heat exchanger 8 is guided by the duct through the air exhaust fan 20 and the indoor air discharge hole 6b and discharged to the outdoor side. In this ventilator, the outdoor air suction hole 4a is formed in one side of one •surface of the casing 2, the indoor air suction hole 6a is formed in the other side of the facing surface of the casing 2, and the outdoor air passage guide 32 and the indoor air passage guide 34 are installed to guide outdoor air and indoor air from the outdoor air suction hole 4a and the indoor air suction hole 6a to the whole exchanger 8, respectively. Accordingly, as illustrated in Fig. 2, outdoor air is sucked directly to A area of the heat exchanger 8 adjacent to the outdoor air suction hole 4a, but curved to be sucked to B area of the heat exchanger 8, and indoor air is sucked directly to B area of the heat exchanger 8 adjacent to the indoor air suction hole 6a, but curved to be sucked to A area of the heat exchanger 8. That is, in order for outdoor air and indoor air to be sucked to the whole heat exchanger 8, outdoor air is partially curved to be g uided to B area of the heat exchanger 8, and indoor air is partially curved to be guided to A area of the heat exchanger 8, thereby generating flow resistances. As a result, air flow efficiency and heat exchange efficiency are reduced. To solve the foregoing problems, the outdoor air suction hole 4a and the indoor air suction hole 6a are designed to be positioned in the centers of one surface and the facing surface of the casing 2, respectively, thereby decreasing flow resistances of outdoor air and indoor air and evenly blowing outdoor air and indoor air through the whole heat exchanger 8. However, when the suction holes 4a and 6a are formed in the centers of the casing 2, the discharge holes 4b and 6b are adjacent to the suction holes 4a and 6a. Therefore, the upwardly-protruded parts of the passage guides 32 and 34 for guiding air sucked from the suction holes 4a and 6a to the heat exchanger 8 are operated as suction flow resistances in the discharge holes 4b and 6b sides. Accordingly, air flow efficiency and heat exchange efficiency decrease. Because the suction holes 4a and 6a are formed in the centers of the -casing 2 and the discharge holes 4b and 6b are formed in the sides of the casing 2, the inside space of the casing where the suction holes 4a and 6a or discharge holes 4b and 6b are not formed is not at all used to flow air. On the other hand, as disclosed in Japanese Laid-Open Patent Application 09-310899 shown in Fig. 3, a heat exchanger 44 for exchanging heat between outdoor air and indoor air is installed to cross a rectangular casing 42, first passages for guiding air flow and a first air blowing means 46 including a fan for generating air streams in the first passages are formed in one side of the casing 42 from the heat exchanger 44, and second passages for guiding air flow and a second air blowing means 47 including a fan for generating air streams in the second passages are formed in the other side of the casing 42 from the heat exchanger 44. Especially, each edge of the casing 42 forms a ridgeline section 42A, a mounting hole 42h is formed on the ridgeline section 42A, a space is formed inside the ridgeline section 42A by a horizontal surface 48a and a vertical surface 48b to the length direction of the heat exchanger 44, an air suction or discharge hole 48h is formed on the horizontal surface 48a to the length direction of the heat exchanger 44, and a duct connection member 49 having a duct connection hole 49a is removably installed on the ridgeline section 42A. Here, the duct connection member 49 can vary the installation direction of the duct according to its installation direction on the ridgeline section 42A of the casing 42. As described above, the ridgeline section 42A is formed on the edge of the casing 42, the space is formed inside the ridgeline section 42A by the horizontal surface 48a and the vertical surface 48b to the heat exchanger 44, and the air suction or discharge hole 48h is formed on the horizontal surface 48a to the heat ^•exchanger 44. Thus, air sucked from one side of the casing 42 passes through the inside space of the ridgeline section 42A, and generates flow resistances. In addition, air sucked from the hole 48h formed in the ridgeline section 42A of the casing 42 evenly flows through the whole heat exchanger 44. Here, air is sucked directly to the heat exchanger 44 adjacent to the hole 48h, but curved to be sucked to the heat exchanger 44 far from the hole 48h, thereby generating flow resistances. As a result, air flow efficiency and heat exchange efficiency are reduced.

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a ventilator which can restrict flow resistances and improve air flow efficiency and heat exchange efficiency, by flowing outdoor air and indoor air in the inclined directions to a heat exchanger on suction passages of a casing. Another object of the present invention is to provide a ventilator miniaturized by reducing an unnecessary space of a casing in which air does not flow. Yet another object of the present invention is to provide a ventilator which allows an operator to easily examine, maintain and repair fans and motors installed inside discharge holes, by appropriately setting positions of the discharge holes and a checking hole and installation directions of the motors in a casing. In order to achieve the above-described objects of the invention, there is provided a ventilator including: a casing having an outdoor air suction hole for sucking outdoor air, an indoor air discharge hole for discharging indoor air, an outdoor air discharge hole for discharging outdoor air and an indoor air suction hole for sucking indoor air; a heat exchanger installed to cross the center of the casing, for dividing the outdoor air suction hole and the indoor air discharge hole from the ^■outdoor a ir d ischarge h ole a nd t he indoor air suction h ole, the h eat e xchanger exchanging heat by separately flowing outdoor air and indoor air through first and second passages; an air supply fan installed on outdoor air passages formed between the outdoor air suction hole and the outdoor air discharge hole, for blowing outdoor air; an air exhaust fan installed on indoor air passages formed between the indoor air suction hole and the indoor air discharge hole, for blowing indoor air; and a means for reducing suction flow loss by setting suction directions of outdoor air or indoor air to have an angle between 0° and 90° to the length direction of the heat exchanger on the suction passages of the casing. According to one aspect of the invention, the casing has at least five side surfaces, and the outdoor air suction hole, the indoor air discharge hole, the outdoor air discharge hole and the indoor air suction hole are foπned on the different side surfaces of the casing. According to another aspect of the invention, the means is formed to incline one surface of the casing where the outdoor air suction hole has been formed to one side surface of the heat exchanger at an angle between 0° and 90°, or to incline one surface of the casing where the indoor air suction hole has been formed to the other side surface of the heat exchanger at an angle between 0° and 90°. According to yet another a spect of the i nvention, the air supply fan i s a sirocco fan installed inside the outdoor air discharge hole, a checking hole is formed on one surface of the casing to slidably disconnect the heat exchanger in the length direction, and a motor for driving the air supply fan is installed toward one surface of the casing where the checking hole has been formed. According to yet another aspect of the invention, the outdoor air discharge hole and the indoor air suction hole are formed in one side of the casing from the heat exchanger, and an indoor air passage guide for guiding indoor air sucked from the indoor air suction hole to the second passages of the heat exchanger is installed in one side of the casing. Here, the motor for driving the air supply fan is installed toward one surface of the casing where the indoor air suction hole is not formed in order to prevent interferences with the indoor air passage guide. The motor is installed to have a predetermined interval from one surface of the casing to flow outdoor air to the air supply fan. The air exhaust fan is a sirocco fan installed inside the indoor air discharge hole, a checking hole is formed on one surface of the casing to slidably disconnect the heat exchanger in the length direction, and a motor for driving the air exhaust fan is installed toward one surface of the casing where the checking hole has been formed for easy examination and repair. According to yet another aspect of the invention, the outdoor air suction hole and the indoor air discharge hole are formed in the other side of the casing from the heat exchanger, and an outdoor air passage guide for guiding outdoor air sucked from the outdoor air suction hole to the first passages of the heat exchanger is installed in the other side of the casing. Here, the motor for driving the air exhaust fan is installed toward one surface of the casing where the outdoor air suction hole is not formed in order to prevent interferences with the outdoor air passage guide. The motor is installed to have a predetermined interval from one surface of the casing to flow indoor air to the air exhaust fan, and a motor checking hole is formed on one surface of the casing to easily disconnect, examine and repair the motor. According to yet another aspect of the invention, the casing further includes a side surface inclined to one side surface of the heat exchanger at an angle between 0° and 90° in the opposite side of the inclined side surface where the -suction hole has been formed. In detail, the casing is formed in the octagonal shape having eight side surfaces, and a checking hole is formed on one side surface of the casing to slidably connect or disconnect the heat exchanger in the length direction. An o utdoor a ir s uction hole is formed o n the side s urface of t he casing adjacent to the checking hole in one side of the casing from the heat exchanger, and an indoor air discharge hole is formed on the side surface adjacent to the side surface where the outdoor air suction hole has been formed. Here, the air exhaust fan is a sirocco fan installed inside the indoor air discharge hole, and a motor for driving the air exhaust fan is installed toward one surface of the casing where the checking hole has been formed for easy examination and repair. In addition, a motor checking hole is formed on the side surface of the casing adjacent to the checking hole in the other side of the casing from the heat exchanger, an outdoor air discharge hole is formed on the side surface adjacent to the side surface where the motor checking hole has been formed, and an indoor air suction hole is formed on the side surface adjacent to the side surface where the outdoor air discharge hole has been formed. Here, the air supply fan is a sirocco fan installed inside the outdoor air discharge hole, and a motor for driving the air supply fan is installed toward one surface of the casing where the motor checking hole has been formed for easy examination and repair. According to yet another aspect of the invention, the means is an outdoor duct connection unit installed in the outdoor air suction hole, inclined to one side surface of the heat exchanger at an angle between 0° and 90°, and connected to a duct, or an indoor duct connection unit installed in the indoor air suction hole, -inclined to one side surface of the heat exchanger at an angle between 0° and 90°, and connected to a duct. The outdoor air suction hole is formed in one side of one surface of the casing, the indoor air discharge hole is formed in the other side thereof, and the air exhaust fan is installed inside the indoor air discharge hole. The outdoor air discharge hole is formed in one side of the facing surface to one surface of the casing, the indoor air suction hole is formed in the other side thereof, and the air supply fan is installed inside the outdoor air discharge hole. Here, a checking hole is formed on one side surface of the casing to slidably d isconnect the heat exchanger in the length direction, a nd a m otor for driving the air supply fan and a motor for driving the air exhaust fan are installed toward one side surface of the casing where the checking hole has been formed. According to yet another aspect of the invention, a bypass damper for opening the passages to discharge air sucked from the indoor air suction hole to the indoor air discharge hole is installed to be opened and closed between the heat exchanger and the casing.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become better understood with reference to the accompanying drawings which are given only by way of illustration and thus are not limitative of the present invention, wherein: Fig. 1 is a perspective view illustrating one example of a conventional ventilator; Fig. 2 is a view illustrating sucked air flow in the conventional ventilator; Fig. 3 is a perspective view illustrating another example of the conventional ventilator; Fig. 4 is a perspective view illustrating a ventilator in accordance with a first embodiment of the present invention; Fig. 5 is a plan view illustrating the ventilator in accordance with the first embodiment of the present invention; Fig. 6 is a view illustrating sucked air flow in the ventilator in accordance with the first embodiment of the present invention; Fig. 7 is a cross-sectional view taken along line A-A of Fig. 5; Fig. 8 is a cross-sectional view taken along line B-B of Fig. 5; Fig. 9 i s a perspective v iew illustrating a v entilator i n accordance w ith a second embodiment of the present invention; Fig. 10 is a plan view illustrating the ventilator in accordance with the second embodiment of the present invention; Fig. 11 is a perspective view illustrating a ventilator in accordance with a third embodiment of the present invention; Fig. 12 is a plan view illustrating the ventilator in accordance with the third embodiment of the present invention; Fig. 13 is a perspective view illustrating a ventilator in accordance with a fourth embodiment of the present invention; Fig. 14 is a plan view illustrating the ventilator in accordance with the fourth embodiment of the present invention; Fig. 15 is a view illustrating sucked air flow in the ventilator in accordance with the fourth embodiment of the present invention; Fig. 16 is a cross-sectional view taken along line C-C of Fig. 14; and Fig. 17 is a cross-sectional view taken along line D-D of Fig. 14.

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Figs. 4 and 5 are a perspective view and a plan view illustrating a ventilator in accordance with a first embodiment of the present invention, Fig. 6 is a view illustrating sucked air flow in the ventilator in accordance with the first embodiment of the present invention, and Figs. 7 and 8 are cross-sectional views taken along lines A-A and B-B of Fig. 5. Referring to Figs. 4 to 8, the ventilator of the first embodiment includes a casing 50 having an outdoor air suction hole 52 for sucking outdoor air, an indoor air discharge hole 54 for discharging indoor air, an outdoor air discharge hole 56 for discharging outdoor air and an indoor air suction hole 58 for sucking indoor air on its different side surfaces, a heat exchanger 60 installed to cross the center of the casing 50, for exchanging heat between outdoor air and indoor air, an air supply blowing means 70 installed inside the outdoor air discharge hole 56, for blowing outdoor air, and an air exhaust blowing means 80 installed inside the indoor air discharge hole 54, for blowing indoor air. The ventilator further includes an outdoor air passage guide 92 installed in the casing 50 in one side of the heat exchanger 60, for guiding outdoor air from the outdoor air suction hole 52 to the bottom of one side surface of the heat exchanger 60, an indoor air passage guide 94 installed in the casing 50 in the other side of the heat exchanger 60, for guiding indoor air from the indoor air suction hole 58 to the bottom of the other side surface of the heat exchanger 60, and a bypass damper 96 installed between the heat exchanger 60 and the casing 50 to be opened and closed, for discharging indoor air from the indoor air suction hole 58 directly to the indoor air discharge hole 54. Here, the casing 50 has six side surfaces so that the outdoor air suction hole 52 and the indoor air discharge hole 54 are formed in one side of the casing 50 from the heat exchanger 60, and the outdoor air discharge hole 56 and the indoor air suction hole 58 can be formed in the facing side thereof. Accordingly, the suction holes 52 and 58 and the discharge holes 54 and 56 are formed on the different side surfaces of the casing 50. That is, the outdoor air suction hole 52 and the indoor air suction hole 58 are formed on the facing surfaces, and the outdoor air discharge hole 56 and the indoor air discharge hole 54 are formed on the facing surfaces. One surface of the casing 50 where the outdoor air suction hole 52 has been formed has an angle between 0° and 90° to one side surface of the heat exchanger 60, so that suction directions of outdoor air to the outdoor air passage guide 92 can be inclined to the length direction of the heat exchanger 60, and one surface of the casing 50 where the indoor air suction hole 58 has been formed has an angle between 0° and 90° to the other side surface of the heat exchanger 60, so that suction directions of indoor air to the indoor air passage guide 94 can be inclined to the length direction of the heat exchanger 60. In addition, one surface of the casing 50 where the indoor air discharge hole 54 has been formed is level with one side surface of the heat exchanger 60, and one surface of the casing 50 where the outdoor air discharge hole 56 has been formed is level with the other side surface of the heat exchanger 60. That is, the casing 50 is formed in the rectangular shape, the two facing edges of the casing 50 are formed on the side surfaces in the inclined directions to the heat e xchanger 60, a nd the o utdoor air s uction h ole 52 a nd t he indoor a ir suction hole 58 are formed on the side surfaces to face each other. Outdoor duct connection units 52a and 54a connected respectively to outdoor ducts (not shown) linked to the outdoor side are vertically protruded from the outdoor air suction hole 52 and the indoor air discharge hole 54, and indoor duct connection u nits 56a a nd 58a connected respectively to indoor ducts (not shown) linked to the indoor side are vertically protruded from the outdoor air discharge hole 56 and the indoor air suction hole 58. On the other hand, the heat exchanger 60 is installed vertically to the side surfaces of the casing 50 where the suction holes 52 and 58 and the discharge holes 54 and 56 are not formed. A checking hole 50h is formed on one side surface of the casing 50 so that the heat exchanger 60 can be slidably connected or disconnected through one side surface of the casing 50, and a checking cover 51 is installed to be connected or disconnected to/from the checking hole 50h. The heat exchanger 60 is formed by alternately stacking first and second heat exchange units 62 and 64 having first and second passages for separately flowing outdoor air and indoor air. A plurality of guide ribs 60b are installed on thin rectangular or hexagonal heat exchange films 60a for flowing outdoor air, and the first and second heat exchange units 62 and 64 are divided according to installation directions of the guide ribs 60b on the heat exchange films 60a. Here, guide protrusions 66a and 66b are protruded long in the length direction from both ends of the heat exchanger 60 to slidably connect or disconnect the heat exchanger 60 to/from the casing 50, guide grooves 92a and 94a are formed long in the length direction in the ends of the outdoor air passage guide 92 and the indoor air passage guide 94 for slidable insertion of the guide protrusions 66a and 66b, and a guide groove 50a is formed long in the length direction on the bottom surface of the casing 50 for slidable insertion of the bottom end of the heat exchanger 60. The heat exchanger 60 is installed to cross the casing 50 to divide one side where the outdoor air suction hole 52 and the indoor air discharge hole 54 have been formed from the other side where the outdoor air discharge hole 56 and the indoor air suction hole 58 have been formed. The air supply blowing means 70 includes an air supply fan 72 rotatably installed inside the outdoor air discharge hole 56, a fan housing 74 for sucking outdoor air to the air supply fan 72 and discharging sucked air to the outdoor air discharge hole 56, a motor 76 for driving the air supply fan 72, and a motor supporting member 78 for fixing the motor 76 to the fan housing 74. A sirocco fan for sucking air in the axial direction and discharging sucked air in the radius direction is used as the air supply fan 72, and the motor 76 is installed toward one surface of the casing 50 where the checking hole 50h has been formed, so that the operator can easily disconnect, examine, maintain and repair the motor 76. The motor 76 can be disconnected with the motor supporting member 74 and part of the fan housing 74. The motor 76 is operated as a suction flow resistance of outdoor air sucked to the fan housing 74. Therefore, the motor 76 is installed to have a predetermined interval from the casing 50, to minimize the suction flow resistance of outdoor air flowing in the space between the motor 76 and the casing 50, and efficiently utilize the inside space of the casing 50. Identically to the air supply blowing means 70, the air exhaust blowing means 80 includes an air exhaust fan 82 which is a sirocco fan rotatably installed inside the indoor air discharge hole 54, a fan housing 84 for sucking indoor air to the air exhaust fan 82 and discharging sucked air to the indoor air discharge hole 54, a motor 86 for driving the air exhaust fan 82, and a motor supporting member 88 for fixing the motor 86 to the fan housing 84. The motor 86 is installed toward one surface of the casing 50 where the checking hole δOh has b een formed. H ere, the motor 86 is installed to have a -predetermined interval to prevent interferences with the upwardly-protruded part of the outdoor air passage guide 92 connected to the outdoor air suction hole 52. When the motor 86 is adjacent to the protruded part of the outdoor air passage guide 92, suction flow resistances of indoor air sucked to the fan housing 84 increase, to reduce air flow efficiency. The outdoor air passage guide 92 is upwardly protruded near the outdoor air suction hole 52 to guide outdoor air sucked from the outdoor air suction hole 52 to the bottom of one side surface of the heat exchanger 60, and downwardly protruded near the indoor air discharge hole 54 to guide indoor air discharged from the top of one side surface of the heat exchanger 60 to the indoor air discharge hole 54. Identically to the outdoor air passage guide 92, the indoor air passage guide 94 is upwardly protruded near the indoor air suction hole 58 to guide indoor air sucked from the indoor air suction hole 58 to the bottom of the other side surface of the heat exchanger 60, and downwardly protruded near the outdoor air discharge hole 56 to guide outdoor air discharged from the top of the other side surface of the heat exchanger 60 to the outdoor air discharge hole 56. In the ventilator of the first embodiment, the outdoor air suction hole 52 and the indoor air suction hole 58 are formed respectively in one side surfaces of the casing 50 inclined to the length direction of the heat exchanger 60. Accordingly, outdoor air and indoor air flow on the suction passages in the inclined directions to the heat exchanger 60 and are smoothly sucked to the whole heat exchanger 60, to minimize flow resistances and improve air flow efficiency and heat exchange efficiency. Moreover, the motors 76 and 86 for driving the air supply fan 72 and the air exhaust fan 82 are installed toward one surface of the casing 50 where the

-checking hole 50h has been formed, so that the operator can easily disconnect, examine, maintain and repair the motors 76 and 86. Figs. 9 and 10 are a perspective view and a plan view illustrating a ventilator in accordance with a second embodiment of the present invention. As illustrated in Figs. 9 and 10, the second embodiment of the present invention is identical to the first embodiment described above. In the air exhaust blowing means 80, the fan housing 84 is installed inside the indoor air discharge hole 54 to be linked to the indoor air discharge hole 54, the air exhaust fan 82 is rotatably installed in the fan housing 84, and the motor 86 for driving the air exhaust fan 82 is fixed to the fan housing 84 by the motor supporting member 88. The motor 86 is installed toward one surface of the casing 50 where the outdoor air suction hole 52 is not formed to prevent inferences with the protruded part of the outdoor air passage guide 92. The motor 86 is operated as a suction flow resistance of indoor air sucked to the fan housing 84. Therefore, the motor 86 is installed to have a predetermined interval from the casing 50, to minimize the suction flow resistance of indoor air flowing in the space between the motor 86 and the casing 50, and efficiently utilize the inside space of the casing 50. Here, the checking hole 5 Oh i s formed on one s urface of the casing 50 adjacent to the surface where the outdoor air suction hole 52 has been formed, so that the motor 86 cannot be disconnected through the checking hole 50h. Thus, a motor c hecking hole δ δh is formed on o ne s urface of the casing 50 facing the motor 86, to easily disconnect, examine, maintain and repair the motor 86. In the air supply blowing means 70, the motor 76 can be installed toward one surface of the casing 50 where the indoor air suction hole 58 is not formed to prevent inferences with the protruded part of the indoor air passage guide 94, and

-a motor checking hole (not shown) can be formed on one surface of the casing 50 facing the motor 76. In the ventilator of the second embodiment, the outdoor air suction hole 52 and the indoor air suction hole 58 are formed in the inclined directions to the length direction of the heat exchanger 60, thereby reducing suction flow resistances of air, and the installation directions of the motors 76 and 86 for respectively driving the fans 72 and 82 inside the outdoor air discharge hole 56 and the indoor air discharge hole 54 are changed to prevent interferences with the protruded parts of the passage guides 92 and 94, thereby reducing discharge flow resistances of air and improving air flow efficiency and heat exchange efficiency. In addition, the checking hole 50h is formed to disconnect the motor 76 for driving the air supply fan 72 and the heat exchanger 60, and the motor checking hole 86h is formed to disconnect the motor 86 for driving the air exhaust fan 82, so that the operator can easily examine, maintain and repair the motors 76 and 86. Figs. 11 and 12 are a perspective view and a plan view illustrating a ventilator in accordance with a third embodiment of the present invention. As depicted in Figs. 11 and 12, the third embodiment of the present invention is identical to the first embodiment described above. The casing 50 has eight side surfaces, and the outdoor air suction hole 52, the indoor air discharge hole 54, the outdoor air discharge hole 56 and the indoor air suction hole 58 are formed on the different side surfaces of the casing 50. In detail, the checking hole 50h is formed on one surface of the casing 50 so that the heat exchanger 60 can be slidably installed to cross the facing surfaces of the casing 50, and the checking cover 51 is installed to be connected or disconnected to/from the checking hole 50h. The outdoor air suction hole 52 and the indoor air discharge hole 54 are formed on the adjacent surfaces in one side of -the casing 50 from the heat exchanger 60, and the outdoor air discharge hole 56 and the indoor air suction hole 58 are formed on the adjacent surfaces in the other side of the casing 50 from the heat exchanger 60. Here, in one side of the casing 50 from the heat exchanger 60, the outdoor air s uction hole 52 i s formed on the s urface adjacent to the surface w here the checking hole 50h has been formed, and the indoor air discharge hole 54 is formed on the other surface adjacent to the surface where the outdoor air suction hole 52 has been formed, and in the other side of the casing 50 from the heat exchanger 60, the indoor air suction hole 58 is formed on the surface adjacent to the facing surface to the checking hole 50h, and the outdoor air discharge hole 56 is formed on the other surface adjacent to the surface where the indoor air suction hole 58 has been formed. Accordingly, air is smoothly sucked to the whole exchanger 60 through the suction passages, to reduce suction flow resistances and improve air flow efficiency and heat exchange efficiency. The side surface of the casing 50 where the outdoor air suction hole 52 and the indoor air discharge hole 54 are not formed is inclined to the length direction of the heat exchanger 60 in one side of the casing 50 from the heat exchanger 60, and the side surface of the casing 50 where the outdoor air discharge hole 56 and the indoor air suction hole 58 are not formed is inclined to the length direction of the heat exchanger 60 in the other side of the casing 50 from the heat exchanger 60, to decrease C and D areas of the casing 50 showing relatively low air flow and miniaturize the product. On the other hand, in the air supply blowing means 70, the motor 76 for driving the air supply fan 72 is installed toward the surface where the checking hole 50h has been formed, and in the air exhaust blowing means 80, the motor 86 for driving the air exhaust fan 82 is installed toward the surface where the checking ^•hole 50h has been formed. The motor 76 for driving the air supply fan 72 is installed adjacently to the casing 50, so that the operator cannot easily disconnect the motor 76 through the checking hole 50h. Therefore, a motor checking hole 76h is formed on the side surface of the casing 50 between the surface where the outdoor air discharge hole 56 has been formed and the surface where the checking hole 50h has been formed. In the ventilator of the third embodiment, the casing 50 has the eight side surfaces, and the outdoor air suction hole 52 and the indoor air suction hole 58 are formed in the inclined directions to the length direction of the heat exchanger 60. As a result, air can smoothly flow on the suction passages, to reduce suction flow resistances and improve air flow efficiency and heat exchange efficiency. In addition, the surfaces of the casing 50 where the suction holes 52 and 58 and the discharge holes 54 and 57 are not formed are inclined to the length direction of the heat exchanger 60, to reduce relatively low air flow areas and miniaturize the product. Furthermore, the checking hole 50h is formed to disconnect the motor 86 for driving the air exhaust fan 82 and the heat exchanger 60, and the motor checking hole 76h is formed to disconnect the motor 76 for driving the air supply fan 72, so that the operator can easily examine, maintain and repair the motors 76 and 86. Figs. 13 and 14 are a perspective view and a plan view illustrating a ventilator in accordance with a fourth embodiment of the present invention, Fig. 15 is a view illustrating sucked air flow in the ventilator in accordance with the fourth embodiment of the present invention, and Figs. 16 and 17 are cross-sectional views taken along lines C-C and D-D of Fig. 14. Referring to Figs. 13 to 17, the ventilator of the fourth embodiment includes -a casing 150 being formed in the rectangular shape having four side surfaces, and having an outdoor air suction hole 152 and an indoor air discharge hole 154 in its one side and an outdoor air discharge hole 156 and an indoor air suction hole 158 in its other side; a heat exchanger 160 installed to cross the center of the casing 150, for exchanging heat between outdoor air and indoor air, an air supply blowing means 170 installed inside the outdoor air discharge hole 156, for blowing outdoor air, an air exhaust blowing means 180 installed inside the indoor air discharge hole 154, for blowing indoor air, an outdoor duct connection unit 152a protruded to be inclined to the outdoor air suction hole 152 at an angle between 0° and 90°, and connected to an outdoor duct (not shown) linked to the outdoor side, and an indoor duct connection unit 158a protruded to be inclined to the indoor air suction hole 158 at an angle between 0° and 90°, and connected to an indoor duct (not shown) linked to the indoor side. The ventilator further includes an outdoor air passage guide 192 installed in the casing 150 in one side of the heat exchanger 160, for guiding outdoor air from the o utdoor a ir s uction h ole 1 52 to the bottom of o ne s ide s urface of t he h eat exchanger 160, an indoor air passage guide 194 installed in the casing 150 in the other side of the heat exchanger 160, for guiding indoor air from the indoor air suction hole 158 to the bottom of the other side surface of the heat exchanger 160, and a bypass damper 196 installed between the heat exchanger 160 and the casing 150 to be opened and closed, for discharging indoor air from the indoor air suction hole 158 directly to the indoor air discharge hole 154. The outdoor air suction hole 152 and the indoor air discharge hole 154 are formed in one side of the casing 150 from the heat exchanger 160, and the outdoor air discharge hole 156 and the indoor air suction hole 158 are formed in the facing side of the casing 150. The outdoor duct connection units 152a and 154a are

^■ protruded respectively from the outdoor air s uction hole 1 52 and the i ndoor air discharge hole 154, and the indoor duct connection units 156a and 158a are protruded respectively from the outdoor air discharge hole 156 and the indoor air suction hole 158. In the casing 150, the outdoor duct connection unit 152a formed on the outdoor air suction hole 152 has an angle between 0° and 90° to one side surface of the heat exchanger 160, so that suction directions of outdoor air to the outdoor air passage guide 192 can be inclined to the length direction of the heat exchanger 160, and the indoor duct connection unit 158a formed on the indoor air suction hole 158 has an angle between 0° and 90° to the other side surface of the heat exchanger 160, so that suction directions of indoor air to the indoor air passage guide 194 can be inclined to the length direction of the heat exchanger 160, to reduce suction flow resistances. In addition, in the casing 150, the outdoor duct connection unit 154a foπned on the indoor air discharge hole 154 is protruded vertically to one side surface of the heat exchanger 160, and the indoor duct connection unit 156a formed on the outdoor air discharge hole 156 is protruded vertically to the other side surface of the heat exchanger 160. That is, the casing 150 is formed in the rectangular shape, and has the outdoor air suction hole 152 and the indoor air discharge hole 154 on its one surface and the outdoor air discharge hole 156 and the indoor air suction hole 158 on its facing surface. The outdoor duct connection unit 152a and the indoor duct connection unit 158a inclined to the length direction of the heat exchanger 160 are formed on the outdoor air suction hole 152 and the indoor air suction hole 158, respectively. A s a result, sucked air can smoothly flow through the whole h eat exchanger 160. On the other hand, the heat exchanger 160 is installed vertically to the side surfaces of the casing 150 where the suction holes 152 and 158 and the discharge holes 154 and 156 are not formed. A checking hole 150h is formed on one side surface of the casing 150 so that the heat exchanger 160 can be slidably connected or disconnected through one side surface of the casing 150, and a checking cover 151 is installed to be connected or disconnected to/from the checking hole 150h. The heat exchanger 160 is formed by alternately stacking first and second heat exchange units 162 and 164 having first and second passages for separately flowing outdoor air and indoor air. A plurality of guide ribs 160b are installed on thin rectangular or hexagonal heat exchange films 160a for flowing outdoor air, and the first and second heat exchange units 162 and 164 are divided according to installation directions of the guide ribs 160b on the heat exchange films 160a. Here, guide protrusions 166a and 166b are protruded long in the length direction from both ends of the heat exchanger 160 to slidably connect or disconnect the heat exchanger 160 to/from the casing 150, guide grooves 192a and 194a are formed long in the length direction in the ends of the outdoor air passage guide 192 and the indoor air passage guide 194 for slidable insertion of the guide protrusions 166a and 166b, and a guide groove 150a is formed long in the length direction on the bottom surface of the casing 150 for slidable insertion of the bottom end of the heat exchanger 160. The air supply blowing means 170 includes an air supply fan 172 rotatably installed inside the outdoor air discharge hole 156, a fan housing 174 for sucking outdoor air to the air supply fan 172 and discharging sucked air to the outdoor air discharge hole 156, a motor 176 for driving the air supply fan 172, and a motor supporting member 178 for fixing the motor 176 to the fan housing 174. A sirocco fan for sucking air in the axial direction and discharging sucked air in the radius d irection is used as the a ir supply fan 172, and the motor 176 i s installed toward one surface of the casing 150 where the checking hole 150h has been formed, so that the operator can easily disconnect, examine, maintain and repair the motor 176. The motor 176 can be disconnected with the motor supporting member 174 and part of the fan housing 174. The motor 176 is operated as a suction flow resistance of outdoor air sucked to the fan housing 174. Therefore, the motor 176 is installed to have a predetermined interval from the casing 150, to minimize the suction flow resistance of outdoor air flowing in the space between the motor 176 and the casing 150, and efficiently utilize the inside space of the casing 150. Identically to the air s upply blowing means 170, the air exhaust blowing means 180 includes an air exhaust fan 182 which is a sirocco fan rotatably installed inside the indoor air discharge hole 154, a fan housing 184 for sucking indoor air to the air exhaust fan 182 and discharging sucked air to the indoor air discharge hole 154, a motor 186 for driving the air exhaust fan 182, and a motor supporting member 188 for fixing the motor 186 to the fan housing 184. The motor 186 is installed toward one surface of the casing 150 where the checking hole 150h has been formed. Here, the motor 186 is installed to have a predetermined interval to prevent interferences with the upwardly-protruded part of the outdoor air passage guide 192 connected to the outdoor air suction hole 152. This is to prevent that When the motor 186 is adjacent to the protruded part of the outdoor air passage guide 192, suction flow resistances of indoor air sucked to the fan housing 184 increase, to reduce air flow efficiency. In the ventilator of the fourth embodiment, the outdoor duct connection unit 152a and the indoor duct connection unit 158a protruded from the outdoor air -suction hole 152 a nd the indoor a ir s uction h ole 1 58 a re inclined to the length direction of the heat exchanger 160. Accordingly, outdoor air and indoor air flow on the suction passages in the inclined directions to the heat exchanger 160 and are smoothly sucked to the whole heat exchanger 160, to minimize flow resistances and improve air flow efficiency and heat exchange efficiency. Moreover, the motors 176 and 186 for driving the air supply fan 172 and the air exhaust fan 182 are installed toward one surface of the casing 150 where the checking hole 150h has been formed, so that the operator can easily disconnect, examine, maintain and repair the motors 176 and 186. The ventilator has been explained in detail on the basis of the embodiments and accompanying drawings of the present invention. However, it is understood that the present invention should not be limited to these preferred embodiments but various changes and modifications can be made by one skilled in the art within the spirit and scope of the present invention as hereinafter claimed.

Claims

What is claimed is:

1. A ventilator, comprising: a casing having an outdoor air suction hole for sucking outdoor air, an indoor air discharge hole for discharging indoor air, an outdoor air discharge hole for discharging outdoor air and an indoor air suction hole for sucking indoor air; a heat exchanger installed to cross the center of the casing, for dividing the outdoor air suction h ole a nd t he indoor a ir d ischarge h ole f rom t he o utdoor air discharge hole a nd the i ndoor air suction hole, the heat exchanger exchanging heat by separately flowing outdoor air and indoor air through first and second passages; an air s upply fan i nstalled o n o utdoor air p assages formed between the outdoor air suction hole and the outdoor air discharge hole, for blowing outdoor air; an air exhaust fan i nstalled on indoor air passages formed between the indoor air suction hole and the indoor air discharge hole, for blowing indoor air; and a means for reducing suction flow loss by setting suction directions of outdoor air or indoor air to have an angle between 0° and 90° to the length direction of the heat exchanger on the suction passages of the casing.

2. The ventilator of claim 1 , wherein the casing has at least five side surfaces, and the outdoor air suction hole, the indoor air discharge hole, the outdoor air discharge hole and the indoor air suction hole are formed on the different side surfaces of the casing.

3. The ventilator of claim 2, wherein the means is formed to incline one surface of the casing where the outdoor air suction hole has been formed to one side surface of the heat exchanger at an angle between 0° and 90°.

4. The ventilator of claim 2, wherein the means is formed to incline one surface of the casing where the indoor air suction hole has been formed to the other side surface of the heat exchanger at an angle between 0° and 90°.

5. The ventilator of claim 3 or 4, wherein the air supply fan is a sirocco fan installed inside the outdoor air discharge hole.

6. The ventilator of claim 5, wherein a checking hole is formed on one surface of the casing to slidably disconnect the heat exchanger in the length direction, and a motor for driving the air supply fan is installed toward one surface of the casing where the checking hole has been formed.

7. The ventilator of claim 5, wherein the outdoor air discharge hole and the indoor a ir suction h ole a re formed in o ne s ide o f the c asing f rom t he h eat exchanger, and an indoor air passage guide for guiding indoor air sucked from the indoor air suction hole to the second passages of the heat exchanger is installed in one side of the casing.

8. The ventilator of claim 7, wherein the motor for driving the air supply fan is installed toward one surface of the casing where the indoor air suction hole is not formed.

9. The ventilator of claim 8, wherein the motor is installed to have a predetermined interval from one surface of the casing to flow outdoor air to the air supply fan.

10. The ventilator of claim 3 or 4, wherein the air exhaust fan is a sirocco fan installed inside the indoor air discharge hole.

11. The ventilator of claim 10, wherein a checking hole is formed on one surface of the casing to slidably disconnect the heat exchanger in the length direction,. and a motor for driving the air exhaust fan is installed toward one surface of the casing where the checking hole has been formed.

12. The ventilator of claim 10, wherein the outdoor air suction hole and the indoor air discharge hole are formed in the other side of the casing from the heat exchanger, and an outdoor air passage guide for guiding outdoor air sucked from the outdoor air suction hole to the first passages of the heat exchanger is installed in the other side of the casing.

13. The ventilator of claim 12, wherein the motor for driving the air exhaust fan is installed toward one surface of the casing where the outdoor air suction hole is not formed.

14. The ventilator of claim 13, wherein the motor is installed to have a predetermined interval from one surface of the casing to flow indoor air to the air exhaust fan.

15. The v entilator of claim 13 or 14, wherein a motor checking hole is formed on one surface of the casing to disconnect and examine the motor.

16. The ventilator of claim 3 or 4, wherein the casing further comprises a side surface inclined to one side surface of the heat exchanger at an angle between 0° and 90° in the opposite side of the inclined side surface where the suction hole has been formed.

17. The ventilator of claim 16, wherein the casing is formed in the octagonal shape having eight side surfaces.

18. The ventilator of claim 17, wherein a checking hole is formed on one side surface of the casing to slidably connect or disconnect the heat exchanger in the length direction.

19. The ventilator of claim 18, wherein an outdoor air suction hole is formed on the side surface of the casing adjacent to the checking hole in one side of the casing from the heat exchanger, and an indoor air discharge hole is formed on the side surface adjacent to the side surface where the outdoor air suction hole has been formed.

20. The ventilator of claim 19, wherein the air exhaust fan is a sirocco fan installed inside the indoor air discharge hole, and a motor for driving the air exhaust fan is installed toward one surface of the casing where the checking hole has been formed.

21. The ventilator of claim 19, wherein a motor checking hole is formed on the side surface of the casing adjacent to the checking hole in the other side of the casing from the heat exchanger, an outdoor air discharge hole is formed on the side surface adjacent to the side surface where the motor checking hole has been formed, and an indoor air suction hole is formed on the side surface adjacent to the side surface where the outdoor air discharge hole has been formed.

22. The ventilator of claim 21 , wherein the air supply fan is a sirocco fan installed inside the outdoor air discharge hole, and a motor for driving the air supply fan is installed toward one surface of the casing where the motor checking hole has been formed.

23. The ventilator of claim 1 , wherein the means is an outdoor duct connection unit installed in the outdoor air suction hole, inclined to one side surface of the heat exchanger at an angle between 0° and 90°, and connected to a duct.

24. The ventilator of claim 1 , wherein the means is an indoor duct connection unit installed in the indoor air suction hole, inclined to one side surface of the heat exchanger at an angle between 0° and 90°, and connected to a duct.

25. The ventilator of claim 23 or 24, wherein the outdoor air suction hole is formed in one side of one surface of the casing, the indoor air discharge hole is formed in the other side thereof, and the air exhaust fan is i nstalled i nside the indoor air discharge hole.

26. The ventilator of claim 25, wherein the outdoor air discharge hole is formed in one side of the facing surface to one surface of the casing, the indoor air suction hole is formed in the other side thereof, and the air supply fan is installed inside the outdoor air discharge hole.

27. The ventilator of claim 26, wherein a checking hole is formed on one side surface of the casing to slidably disconnect the heat exchanger in the length direction, and a motor for driving the air supply fan and a motor for driving the air exhaust fan are installed toward one side surface of the casing where the checking hole has been formed.

28. The ventilator of any one of claims 1 to 27, wherein a bypass damper for opening the passages to discharge air sucked from the indoor air suction hole to the indoor air discharge hole is installed to be opened and closed between the heat exchanger and the casing.