专利摘要:

公开号:SE1000435A1
申请号:SE1000435
申请日:2010-04-29
公开日:2011-07-26
发明作者:Mike Hoeglund;Andreas Pfister;Elisabet Ehn;Lai Kim Lim
申请人:Dryvent Solutions Of Scandinavia Ab;
IPC主号:
专利说明:

SUMMARY OF THE INVENTION An aspect of the invention at least partially addresses the above with a system for venting a confined space, of which at least one indoor sensor is arranged to measure temperature and relative humidity in the delimited space, at least one outdoor sensor is arranged to measure temperature. and relative humidity outside the confined space, a controllable fan adapted to ventilate the delimited space, and a control unit connected to the at least one indoor sensor, at least one outdoor sensor and the controllable fan, the control unit being configured to determine the absolute steam content within the delimited space and the absolute steam content outside the delimited space, where the control unit is further configured to operate the controllable fan if the absolute steam content outside the delimited space is lower or equal to the absolute steam content inside the delimited space, and the temperature in the delimited space the temperature is above a predefined temperature limit value when the temperature outside the delimited space is below the temperature in the delimited space.
The present invention is based on the insight that controlled forced ventilation may be advantageous based on a comparison of absolute vapor content "indoors" and absolute vapor content "outdoors" instead of being controlled on the corresponding relative humidity in / outside the confined space, which is the case. with some previous systems. By using the absolute steam content inside / outside the delimited space, the reliability of the system increases and thus the possibility of protecting the delimited space from e.g. moisture-related problems and / or damage.
In addition, and as noted above, the confined space is not ventilated if the indoor temperature is lower than a predefined temperature limit value and if the outdoor temperature is lower than the indoor temperature. This temperature limit value is preferably in the range 3 - 10 ° C, or preferably between 4 - 8 ° C or most preferably between 5 - 6 ° C. This increases the energy efficiency of the system further as it has been established that it is not necessary to ventilate the delimited space. when these temperature thresholds are lowered, i.e. when the indoor temperature is, for example, below 3 - 10 ° C, there are no moisture problems and / or damage. When it is not necessary to ventilate the delimited space below the predefined temperature limit value exemplified above, hot air inside the crawl space will not be ventilated away, which would otherwise affect other spaces, for example living areas adjacent to the delimited space. In some cases, however, it may be necessary / appropriate to also ventilate the delimited area, even if the indoor temperature is lower than the predefined temperature limit value. In such cases, however, it is desirable to ventilate in a restrictive manner, possibly for shorter periods of time.
The enclosed, or at least partially enclosed, confined space is preferably a basement, crawl space, attic, a storage room, a caravan, a trailer and a cabin. Another demarcated place that is sensitive to moisture damage is the spaces inside boats. In particular, engine rooms and interiors of boats stored in marinas can easily become moldy, giving the boats a musty odor and damaging the interior of the boats.
In a preferred design, the system consists of at least two outdoor sensors located on opposite sides of the delimited space, for example an outdoor sensor is mounted on the north side of the delimited space and a sensor is mounted on the south side of the delimited space. Additional sensors, inside and / or outside the delimited space may of course be possible and within the scope of the invention. In addition, by providing the system with at least one controllable valve connected to the control unit, for example two controllable valves mounted on the north and south sides of the delimited space, the system is configured to be able to control the ventilation in the delimited space, and thus it can be possible to ventilate the delimited space with air from the side of the delimited space where the conditions are currently most favorable.
In some cases, it is also possible to completely close the at least one adjustable valve if the absolute steam content outside the delimited space is higher than the absolute steam content inside the delimited space.
In some cases it is also possible to equip the system with a dehumidifier which is connected to and controlled by the control unit, where the control unit can be configured to close the at least one controllable valve and operate the dehumidifier if the relative humidity inside the delimited space exceeds a predefined limit value, where the limit value of the relative humidity is preferably between 50 - 85%, preferably between 55 - 75% and most preferably between 60 - 70%. Operating the dehumidifier may be necessary if conditions are very unfavorable and obvious moisture-related problems may exist. Such conditions may, for example, relate to specific weather conditions and / or construction technical problems.
Preferably, the system comprises a storage mechanism which is connected to the control unit and configured to store data from the indoor and / or outdoor sensor (s). The storage can for example be digital storage such as e.g. a USB or flash memory card, such as CompactFlash, Memory Stick, Secure Digital etc. and the homeowner or any other valid or possibly valid user can use the data to get an overview of the conditions in the delimited space for a longer period of time, e.g. over a month, quarter, year and so on in order to assess the structural integrity of the house.
Alternatively or additionally, the storage can be connected to a remote server where the information from the sensor (s) is stored. Thus, other users, such as potential home buyers, brokers, etc. can gain access to the information and thereby draw conclusions about the health of the home. The data transmission can be via wired network or wireless, for example wired connections such as USB, FireWire, VGA, or similar, and wireless connection such as WLAN, CDMA, GSM, GPRS, 3G mobile communication, 4G mobile communication, Bluetooth, 1R or similar.
According to another aspect of the present invention, there is provided a method of venting a confined space. The method comprises measures for measuring temperature and relative humidity within a delimited space by means of at least one indoor sensor, measuring temperature and relative humidity outside the delimited space by means of at least one outdoor sensor, determining the absolute vapor content within the delimited space, determining the absolute vapor content outside the defined space, and operate a fan if the absolute vapor content outside the confined space is lower or equal to the absolute vapor content within defined space, and the temperature in the defined space is above a predefined temperature limit value when the temperature outside the defined space is below the temperature in the delimited space. This aspect of the invention provides similar advantages as discussed above over the previous aspect of the invention.
Additional features and advantages of the present invention will become apparent upon study of the appended claims and the following description. One skilled in the art will recognize that various features of the present invention may be combined to create additional constructions other than those described below, without departing from the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS The various aspects of the invention, including its features and advantages, will be readily understood from the following detailed description and accompanying drawings, in which: Fig. 1 conceptually illustrates a presently preferred embodiment of the system for venting a confined space, and Fig. 2 shows a schematic flow diagram of a presently preferred method of venting a confined space.
DETAILED DESCRIPTION The present invention is described in more detail below with reference to the accompanying drawings, in which a presently preferred embodiment of the invention is shown. However, the invention may be embodied in many different forms and should not be construed as limited by the embodiment described herein; instead, these embodiments are attached for thoroughness and completeness, and thus convey the full scope of the invention to one skilled in the art.
Referring now to the drawings and to Fig. 1 in particular, there is shown a system 100 for venting a confined space, such as a crawl space 102. The system 100 includes an indoor sensor 104, for example, centrally mounted within the crawl space 102 and a first and second outdoor sensors. 106, 106 'which are mounted on opposite sides 1028, 102b outside the crawl space 102. The inner 104 and outdoor sensors 106, 106' may be of the same type, or be specially adapted depending on their location, e.g. with different water protection, protective cover. Each of the sensors 104, 106, 106 'is configured to measure the temperature (Tinne / Uje) and the relative humidity (RHmne / ute) at their respective locations. The sensors 104, 106, 106 'may contain a combination of sensors for sensing temperature and humidity, or may be combined into a single element.
The system 100 also includes a controllable fan 108 which is adapted to ventilate the confined space. The fan 108 is advantageously mounted in the vicinity of a ventilation hole V1 in the crawl space 102 and is configured to provide an amount of ventilation which depends, for example, on the volume / area of the crawl space 102, for example by means of speed control of the fan 108. The fan 108 can operate in two directions , e.g. to draw air from the outside of the delimited space 102 into the delimited space 102, or to draw air from inside the delimited space 102 out to the outside of the delimited space 102. The chosen direction depends, for example, on the type of delimited space 102, where e.g. is advantageous to draw air out of a crawl space, but at the same time to draw air into a wind.
The system further includes a controller 110 which is connected to the indoor and outdoor sensors 104, 106 and 106 'and the fan 108. The connection between the sensors 104, 106 and 106', the fan 108 and the control unit 110 may be provided with cables or be wireless (for example Bluetooth , IR, ZigBee or the like). The controller 110 may include a microprocessor, a microcontroller, a programmable digital signal processor, or other programmable device. The controller 110 may also, or instead of, include a dedicated integrated circuit (ASIC), a programmable gate matrix with programmable matrix logic, a programmable logic device or a digital signal processor. When the control unit 110 contains a programmable unit such as e.g. a microprocessor or microcontroller mentioned above, the processor may comprise additional code that controls the operation of the programmable device.
The controller 110 is further coupled to a logging mechanism, such as a memory 116 which is configured to store data from sensors and / or operating periods and speed of the fan 108. Alternatively or additionally, the controller 110 may be provided with a communication module 118 for sending the stored data, e.g. . to a server (not shown). Fig. 1 also shows a number of additional ventilation holes V2, V3, V4 and V5 where two ventilation holes are located on opposite sides 1022., 102b of the crawl space 102 and are connected to the first and second outputs 106, 106 ". The opposite sides 1028, 102b of the crawl space 102 may, for example, represent the north and south sides of a building where the crawl space 102 forms a foundation. Each or at least some of the ventilation holes V2, V3, V4 and V5 can be equipped with valves 112 which are connected and controlled by the control unit 110. The valves 112 can be configured to be controlled individually and to be able to be opened to different levels. More (or fewer) ventilation holes, valves and outdoor sensors can of course be used e.g. one outdoor sensor per ventilation hole / valve.
Some embodiments of the system 100 may also consist of a dehumidifier 114 installed inside the crawl space 102 and controlled by the control unit 110, such as, for example, a mechanical / condensate dehumidifier or a sorption dehumidifier. The type of dehumidifier 112 may, for example, depend on the expected temperature inside the confined space, where mechanical / condensate dehumidifiers generally only work at temperatures above 12 ° C. When a dehumidifier 114 is used, water generated by the dehumidifier 114 can be discharged from the crawl space 102 using, for example, a pipe or hose (not shown).
Fig. 2 shows a schematic flow diagram of a presently preferred method of operating the system 100 for venting the crawl space 102.
The process starts in steps S1 and S2, where the control unit 110 collects values of the temperature Twins / outside, And the relative humidity, RHinne / ule from inside and outside the crawl space 102 by means of the indoor sensor 104 and the outdoor sensors 106, 106 ”. Followed * by the collection of the temperature Tinne / ule, and the relative humidity, RHmne / uje, the control unit in steps S3 and S4 determines the value of the absolute vapor content AHmne / out for each of the sensors 104, 106 106 ”. Ie. in the embodiment shown in Fig. 1, inside the crawl space 102, the sensors on the north side 1023 outside the creep ground and on the south side 102 b outside the creep ground 102. are referred to. The control unit 110 can determine the absolute steam content, AHinne / uie for each of the sensors 104, 106, 106 'by an approximate calculation or by using, for example, a Mollier diagram adapted for the control unit 110. Depending on the results of the calculation of the absolute vapor content AHinne / uie for each of the sensors 104 , 106, 106 ', the controllable fan can be operated, S5, to ventilate the crawl space 102. The general condition for ventilating the crawl space 102 depends on whether the absolute steam content AHeie outside the crawl space 102 is lower or equal to the absolute steam content AHime inside the crawl space 102, and furthermore that the temperature Time inside the creeping ground 102 is above a predefined temperature limit value when the temperature Ture outside the creeping ground 102 is lower than the temperature Time inside the creeping ground 102. In the preferred embodiment of the system 100 shown in Fig. 1 and provided in a crawl space 102, the temperature limit value is around 5-6 ° C and the conditions on each of the sides 102e, 102b outside the crawl space are taken into account. This means that on a cold but sunny day when the sun only shines on the south side 102b, the conditions on the north side 102e may be such that the general conditions above are not met, for example if you take the average conditions on the north side and south side , 102e, 1021 ,.
On the other hand, if one only compares the conditions on the south side 102e, the conditions for operating the fan 108 and ventilating the crawl space may be met. If there are valves 112 mounted in the ventilation holes V2, V3 on the north side 102e, these can be closed. When driving the fan 108, only air will be drawn into the crawl space 102 through the ventilation openings V4, V5 on the south side 102b where the valves 112 are open. Other ways of controlling the valves 112 and the fan 108 can of course be used, for example where the valves 112 are run individually so that the crawl space 102 is ventilated in the most advantageous manner in accordance with the general conditions of the invention. The retrieval, 81/82, and the determination 83/84 are advantageously made periodically, for example every minute or hour. Accordingly, the best possible ventilation can be created for the crawl space 102. In addition, substantially parallel to steps 81-85, the control unit can also have another step 86 performed where the values obtained by the sensors 104, 106, 106 'together with speed / the running time of the fan 108 is stored. Although the invention has been described with reference to specific exemplary embodiments, many different variations, modifications, and the like will become apparent to those skilled in the art. Variations to the accompanying embodiments may be understood and practiced by one skilled in the art in the practice of the invention by studying drawings, descriptions and the appended claims. For example, in the above description of the ventilation system, a number of parts, for example valves, dehumidifiers, etc. have been included with a system. However, the system does not have to contain all the parts shown above at all times, but instead only some of these parts are necessary to be able to exhibit at least the basic functions of the invention as defined by the claims below.
In some cases, the conditions in a crawl space are also so unfavorable that it is necessary to operate the dehumidifier, for example if the relative humidity, RHinne reaches 70 - 75%. When this happens, it can be beneficial to close all valves. Furthermore, in cases where the fan has a valve (not shown), it is also advantageous to close this valve.
In addition, in the claims, the word "include" does not mean that other parts or steps are excluded, and the definite form "one" or "one" does not exclude that there may be several of the same type.
权利要求:
Claims (10)
[1]
A system (100) for ventilating a confined space (102), comprising: - at least one indoor sensor (104) arranged to measure temperature (Tinne) and relative humidity (RHmne) within the delimited area (102); - at least one outdoor sensor (106) arranged to measure temperature (Inches) and relative humidity (RHuie) outside the confined space (102); - a controllable fan (108) adapted to ventilate the confined space (102); and - a control unit (110) connected (the) at least one indoor sensor (104), the at least one outdoor sensor (106) and the controlled fan (108), the control unit (110) being configured to determine absolute vapor content (AHmne) inside the bounded space (102) and absolute steam content (AHme) outside the bounded space (102), the control unit (110) being further configured to drive the controllable fan (102) if: - the absolute steam content (AHuie) outside the bounded space ( 102) is lower than or equal to the absolute vapor content (AHmne) inside the confined space, and - the temperature (Tinne) inside the confined space (102) is above a predefined temperature limit value when the temperature (Tmne) outside the confined space (102) is lower than the temperature (Tmne) inside the confined space (102).
[2]
A system (100) according to claim 1, wherein the predetermined temperature limit value is within 3 - 10 ° C, preferably within 4 - 8 ° C most preferably within 5 - 6 ° C.
[3]
A system (100) according to claim 1 or 2, wherein the delimited space (102) is selected from a group of spaces consisting of basement, crawl space, attic, storage, caravan, trailer or cottage. 10 15 20 25 30 11
[4]
A system (100) according to any one of the preceding claims, wherein the system (100) comprises at least two outdoor sensors (106, 106 ') located on opposite sides (1028, 102b) of the delimited space (102).
[5]
A system (100) according to any one of the preceding claims, wherein the system (100) comprises at least one controllable valve (112) coupled to the control unit (110), and the control unit (110) is configured to close the (at least one) valve ( 112) if the absolute vapor content (AHuie) outside the confined space (102) is higher than the absolute vapor content (AHmne) inside the confined space (102),
[6]
The system (100) of claim 5, wherein the system (100) comprises a dehumidifier (114) coupled and controlled by the control unit (110), the control unit (110) being configured to close the (at least one) valve (112). and operating the dehumidifier (114) if the relative humidity (RHmne) within the defined space (102) is higher than a predetermined relative humidity limit value.
[7]
A system (100) according to claim 6, wherein the predetermined relative humidity limit value is within the range 50 - 85%, preferably between 55 - 75% and most preferably between 60 - 70%.
[8]
A system (100) according to any one of the preceding claims, wherein the system (100) also consists of a user-accessible storage unit (116) which is connected to a control unit (110) and is configured to store the data from indoor and / or outdoor sensors (s). ) (104, 106, 106 ').
[9]
A method of ventilating a confined space (102), the method comprising the steps of: - collecting data in the form of (S1) temperature (Tin) and relative humidity (RHinne) within the delimited space (102) using at least one encoder (104); Collecting data in the form of (S2) temperature (Tute) and relative humidity (RHme) outside the confined space (102) using at least one outdoor sensor (106); - determining (S3) the absolute vapor content (AHmne) within the defined space (102); - determining (S4) the absolute vapor content (AHufe) outside the confined space (102); and - operating (S5) a controllable fan (102) if: - the absolute vapor content (Ål slope) outside the defined space (102) is lower than or equal to the absolute vapor content (AHmne) inside the defined space, and the temperature ( Tin) inside the confined space (102) is above a predefined temperature limit value when the temperature (Time) outside the delimited space (102) is lower than the temperature (Tinne) inside the delimited space (102).
[10]
The method of claim 9, further comprising the step of storing (S6) data from indoor and / or outdoor sensor (s) (104, 106, 106 ').
类似技术:
公开号 | 公开日 | 专利标题
SE1000435A1|2011-07-26|System and method for ventilating a confined space
US5881951A|1999-03-16|Ventilator for beneath enclosed structures
Al-Obaidi et al.2014|A review of the potential of attic ventilation by passive and active turbine ventilators in tropical Malaysia
US20060283963A1|2006-12-21|Monitoring system
KR101267633B1|2013-05-27|The control system of optimum sensory temperature with humidity criterion
US20140206278A1|2014-07-24|Automated fresh air cooling system
US5626288A|1997-05-06|Process and apparatus for ventilating an enclosed space
JP4108682B2|2008-06-25|Indoor environment control method for buildings with ventilation insulation structure
ES2808625T3|2021-03-01|Exhaust ventilation device and method
SE0702099A1|2010-06-08|Dehumidifying ventilation and control of air flow in confined spaces
US20110253359A1|2011-10-20|System and method for sensing air flow, carbon dioxide or volatile organic compound in residential building
US20050269418A1|2005-12-08|Monitoring system
US6145750A|2000-11-14|Ventilator for beneath enclosed structures
EP2652411A1|2013-10-23|An adjustable building ventilator
KR100995648B1|2010-11-19|An Equipment of a ventilating used in house
JP4751363B2|2011-08-17|Floor heating system
JP5221994B2|2013-06-26|Geothermal indoor air conditioning system
ES2643149T3|2017-11-21|Installation of mechanical ventilation due to hygienic insufflation and associated procedure
CN202561949U|2012-11-28|Base station intelligent air ventilating and energy saving system
RU2716881C2|2020-03-17|Ventilation plants control system, ventilation plant containing such control system, and set
AU2004284460B2|2007-06-21|Monitoring system
SE0702095A0|2009-03-19|Adaptive fan control for drying and vacuuming of spaces
JP2007224642A|2007-09-06|Underfloor system
Shurcliff1988|Air-to-air heat-exchangers for houses
JP2008039314A|2008-02-21|Ventilation system
同族专利:
公开号 | 公开日
SE534370C2|2011-07-26|
US20130040550A1|2013-02-14|
FI20126173A|2012-11-09|
WO2011136713A1|2011-11-03|
NO20121200A1|2012-10-16|
CA2796658A1|2011-11-03|
引用文献:
公开号 | 申请日 | 公开日 | 申请人 | 专利标题

US3694925A|1970-09-04|1972-10-03|Acf Ind Inc|Humidity control in a temperature controlled railway car|
US3739487A|1971-01-28|1973-06-19|R Clark|Drying apparatus|
US4136822A|1976-08-05|1979-01-30|Felter John V|Apparatus and methods for controlling fan operation|
US4964566A|1988-10-14|1990-10-23|Custom Industries, Inc.|Forced air ventilating device|
US5082173A|1989-02-22|1992-01-21|Mcmaster University|Environmental controller for a sealed structure|
US5000381A|1989-03-30|1991-03-19|Raytheon Company|Window fan with controller|
JPH0544969A|1990-07-17|1993-02-23|Awaa Bureen Kankyo Sekkei Kk|Room ventilating system|
US5092520A|1990-11-30|1992-03-03|Air-Tech Equipment Ltd.|Household dehumidifier|
US5253804A|1992-05-12|1993-10-19|Sarazen Jr Paul M|Temperature and humidity sensitive high efficiency exhaust ventilator apparatus|
US5294049A|1993-02-22|1994-03-15|Temp-Vent Corporation|Power temp vent duct system|
EP0917677B1|1996-08-09|2002-12-11|Ray Hudson Limited|Ventilation controlling apparatus|
US6145750A|1997-09-18|2000-11-14|Carpenter; Peter W.|Ventilator for beneath enclosed structures|
US5881951A|1997-09-18|1999-03-16|Carpenter; Peter W.|Ventilator for beneath enclosed structures|
CA2265067A1|1998-03-09|1999-09-09|Grant Reuter|Module-controlled building drying system and process|
US6468054B1|1999-10-28|2002-10-22|Christopher L. Anthony|Crawl space ventilator fan|
US6514138B2|2001-01-09|2003-02-04|Kevin Estepp|Demand ventilation module|
US6935570B2|2002-09-03|2005-08-30|Phillip F. Acker|Ventilation system with humidity responsive ventilation controller|
US6826920B2|2002-12-09|2004-12-07|Honeywell International Inc.|Humidity controller|
US6958010B1|2004-04-22|2005-10-25|Tb&B Partners|Crawl space ventilation system|
US7264649B1|2004-07-23|2007-09-04|Advanced Design Consulting Usa, Inc.|System for allergen reduction through indoor humidity control|
US10197297B2|2005-09-23|2019-02-05|II William B. Daniels|Passive ventilation control system|
US7758408B2|2006-06-01|2010-07-20|Ventotech Ab|Dehumidifying ventilation and regulation of airflow in enclosed structures|
US8463492B2|2008-05-28|2013-06-11|Chrysler Group Llc|Efficient AC operation using dew-point temperature|
US8463444B2|2009-06-08|2013-06-11|Josmon C. George|Environment control system|
US8467905B2|2009-06-08|2013-06-18|Josmon C. George|Environment control system|US8567688B2|2003-07-16|2013-10-29|Andrew R. Weisenberger|Moisture reduction and mold and moisture damage preventative system and method in construction|
AU2011235604B2|2010-03-31|2015-09-17|Sisacs Holdings Ltd|Super integrated security and air cleansing systems |
AT513405A1|2012-08-20|2014-04-15|Theodor Ernst Seebacher|Combined dehumidifier & fan air heater|
US9582011B2|2012-09-14|2017-02-28|Paul Stuart & Associates, Llc.|Integrated attic ventilation, air conditioning and heating system electronic controller and system and method for use of same|
US10520205B2|2013-03-13|2019-12-31|Digi International Inc.|Thermostat|
WO2014182724A1|2013-05-06|2014-11-13|Green Revolution Cooling, Inc.|System and method of packaging computing resources for space and fire-resistance|
US10928084B2|2017-04-14|2021-02-23|Johnson Controls Technology Company|Multi-function thermostat with intelligent supply fan control for maximizing air quality and optimizing energy usage|
US10866003B2|2017-04-14|2020-12-15|Johnson Controls Technology Company|Thermostat with preemptive heating, cooling, and ventilation in response to elevated occupancy detection via proxy|
WO2018191688A2|2017-04-14|2018-10-18|Johnson Controls Techology Company|Thermostat with exhaust fan control for air quality and humidity control|
US10712038B2|2017-04-14|2020-07-14|Johnson Controls Technology Company|Multi-function thermostat with air quality display|
US10731885B2|2017-04-14|2020-08-04|Johnson Controls Technology Company|Thermostat with occupancy detection via proxy measurements of a proxy sensor|
EP3610203A4|2017-04-14|2021-01-06|Johnson Controls Technology Company|Multi-function thermostat with intelligent ventilator control for frost/mold protection and air quality control|
US11131474B2|2018-03-09|2021-09-28|Johnson Controls Tyco IP Holdings LLP|Thermostat with user interface features|
法律状态:
2016-11-29| NUG| Patent has lapsed|
优先权:
申请号 | 申请日 | 专利标题
SE1000435A|SE534370C2|2010-04-29|2010-04-29|System and method for ventilating a confined space|SE1000435A| SE534370C2|2010-04-29|2010-04-29|System and method for ventilating a confined space|
CA2796658A| CA2796658A1|2010-04-29|2011-04-29|System and method for ventilating a defined space|
US13/641,525| US20130040550A1|2010-04-29|2011-04-29|System and method for ventilating a defined space|
PCT/SE2011/000075| WO2011136713A1|2010-04-29|2011-04-29|System and method for ventilating a defined space|
NO20121200A| NO20121200A1|2010-04-29|2012-10-16|System and method for ventilation of a defined area|
FI20126173A| FI20126173A|2010-04-29|2012-11-09|System and method for ventilating a confined space|
[返回顶部]