Abstract:
A flood gate for use in a foundation crawl space and the like comprises a frame having side walls defining a fluid passageway therethrough, a door pivotally mounted in the frame for bidirectional rotation between two open positions and a closed position therebetween to permit tidal water flow therethrough, and at least one catching assembly for holding the door in the closed position against a minimum level of pressure of the tidal water flow. Tidal flood waters exceeding the minimum pressure level are automatically vented through the crawl space and the like reducing a risk of structural damage from the tidal flood waters. The flood gate can further comprise a door having a ventilation opening, an automatic louver assembly for controlling air flow through the opening, and a screen covering the opening. The automatic louver assembly opens and closes responsive to ambient temperature.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This is a Continuation-In-Part of application Ser. No. 09/079,611 filed May 15, 1998, U.S. Pat. No. 5,944,445. Application Ser. No. 09/079,611 claims the benefit of provisional application No. 60/052,819 filed July 10, 1997. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to crawl space and basement venting, and in particular, to the flood venting of enclosed spaces within a foundation. 
     2. Description of Related Art 
     Building Officials and Code Administrators (BOCA) regulations mandate that buildings with subgrade level, enclosed spaces, such as crawl spaces, located in low-lying coastal flood areas, provide for adequate relief from tidal flood waters stemming from oncoming tides and receding waters. As a solution to the problem of tidal flood waters, local regulations and good construction practice employ the use of venting. However, while venting allows for tidal waters to ebb and flow through the enclosed space, the venting should not allow access by small animals, insects, and other pests through the openings in the enclosed space. In particular, BOCA regulations require flood venting for all new construction in low lying coastal flood areas. Furthermore, NOCA regulations require the use of flood venting where renovations to an existing structure exceed fifty percent of the value of the property. 
     Notwithstanding, good construction practice also embraces the use of vents which can be opened during warmer months to allow for air ventilation to permit moisture to escape from crawl spaces, while retaining the ability to close during colder months to prevent the circulation of cold air around exposed plumbing in crawl spaces. Thus, because the use of screening and louvers is necessary to achieve both the warm weather and cold weather requirements of proper venting, a flood vent must be able to automatically remove the louver and screen barrier when confronted with free flowing tidal flood water. 
     Generally, a wide variety of devices have been developed which may be utilized to provide pressure relief from both liquid and gaseous forces. With respect to gas pressure relief devices, U.S. Pat. No. 3,680,239, issued Aug. 1, 1972 to Burtis for PRESSURE EQUALIZING VALVE, discloses a device to relieve overpressure and underpressure in the opening and closing of a door of a refrigerated space. U.S. Pat. No. 2,774,116, issued Dec. 18, 1956 to Wolverton for DOUBLE ACTING RELIEF VALVE, U.S. Pat. No. 2,798,422, issued Jul. 9, 1957 to Bourque for AIR RELIEF MEANS FOR DOORS, and U.S. Pat. No. 3,123,867, issued Mar. 10, 1964 to Combs for VESTIBULE PRESSURE EQUALIZER relate to the equalization of differential air pressure experienced in the swinging of one door relative to another door. Additionally, U.S. Pat. No. 2,105,735, issued Jan. 18, 1938 to Hodge for PRESSURE RELEASING APPARATUS, and U.S. Pat. No. 4,116,211, issued Sept. 26, 1978 to Kamezaki for AIR PRESSURE CONTROL APPARATUS FOR A HOT OR COLD STORAGE CHAMBER, teach methods to release pressure in closed chambers resulting from changing temperatures within the chamber. In particular, the Kamezaki apparatus utilizes a swinging damper hinged at the top of an enclosing frame. Nevertheless, neither the Kamezaki apparatus nor other inventions contemplate the use of a vented damper able to relieve pressure resulting from fluid flow. 
     Correspondingly, several devices have been developed which provide relief from overpressure resulting from the flow of water and other liquids. U.S. Pat. No. 4,349,296, issued Sept. 14, 1982 to Langeman for IRRIGATION DITCH GATE describes a gate for an irrigation ditch, which during normal conditions through the use of tensioned springs, maintains flood gates in a closed position, but upon flood conditions, allows for the gates to open. U.S. Pat. No. 3,939,863, issued Feb. 24, 1976 to Robison for BASEMENT SUMP CONSTRUCTION discloses a basement drain containing a trap for the prevention of back flow of flood water. U.S. Pat. No. 4,174,913, issued Nov. 20, 1979 to Schliesser for ANIMAL GUARD FOR FIELD PIPE relates to an invention which, while allowing for the free-flow exit of debris carrying effluents from an open pipe end, prevents animal entry into the pipe. Still, none of the aforementioned devices contemplate the integration of a liquid flow control device with a temperature controlled ventilation system. 
     Presently, several patents disclose methods for ventilating enclosed foundation spaces. U.S. Pat. No. 5,293,920, issued Mar. 15, 1994 to Vagedeg for LOUVERED BASEMENT VENT, and U.S. Pat. No. 5,487,701, issued Jan. 30, 1996 to Schedegger et al. for PLASTIC FOUNDATION VENT, embody louvered basement vents which can be manually adjusted to limit air flow in colder temperatures, and to maximize air flow in hotter conditions. U.S. Pat. No. 5,460,572, issued Oct. 24, 1995 to Waltz et al. for FOUNDATION ventilator discloses merely a one-piece molded plastic foundation ventilator without louvers. The Waltz invention, however, contemplates the manual use of hinged doors to regulate air flow through to the foundation. U.S. Pat. No. 2,754,747, issued Jul. 17, 1956 to Bertling for AIR REGISTER OR LOUVER, embodies a hinged, louvered door, designed to facilitate the maintenance of the screen behind the louvered door. Nonetheless, the louvers are designed to be operated manually by the user. 
     All of the aforementioned foundation ventilators contain screening to prevent small animals, insects and other pests from gaining access to the enclosed area. Significantly, none of the aforementioned foundation ventilators will act as a water pressure relief valve in response to the ebb and flow of tidal waters. Furthermore, none provide for the automatic adjustment of louvers in response to increasing or decreasing temperature so as to prevent either the rotting of the elements of the structure&#39;s foundation, or the freezing of pipes within the enclosed space. Accordingly, the prior art has not provided an integrated method to automatically ventilate an enclosed space of a foundation while allowing for the relief of liquid pressure on either side of the vent, and preventing small animals, insects and pests from entering the enclosed space. 
     SUMMARY OF THE INVENTION 
     The subject invention has advantages over all current air vents now used and provides a novel and nonobvious opening for the entry and exit of tidal flood waters. The maintenance free flood vent can be installed in new and existing crawl spaces and foundations and can remain in use year round. These vents have particular utility in areas designated by the Federal Emergency Management Agency (FEMA) as low lying, flood areas. When installed, the vent will allow for the free passage of air ventilation in warm temperatures and the temperature controlled louvers will close fully in colder temperatures. 
     Also, the louvered panel will be screened to prevent penetration by small animals, insects, and other pests and will operate like a pivotally connected gate. The panel can be secured in the closed position by a latching mechanism that senses the height of water surrounding the vent and releases the panel at a predetermined height. 
     A vent in accordance with an inventive arrangement can remain open for regular air ventilation in warm weather conditions, can close to block off air flow during cold weather conditions and can, at any time, open to enable the passage of flood water into and out of the crawl space. 
     A flood gate for use in a foundation crawl space and the like comprises a frame having side walls defining a fluid passageway therethrough, a door pivotally mounted in the frame for bidirectional rotation between two open positions and a closed position therebetween to permit tidal water flow therethrough, and at least one latching mechanism, for holding the door in the closed position against a minimum level of water, whereby waters exceeding the minimum water height are automatically vented through the crawl space and the like reducing a risk of structural damage from the tidal flood waters. A flood gate advantageously comprises a door having a ventilation opening, an automatic louver assembly for controlling air flow through the opening, and a screen covering the opening. An automatic louver assembly opens and closes responsive to ambient temperature. 
     A method for integrating ventilation of an enclosed space and relief from tidal flooding of an enclosed space comprises the steps of: maintaining a vent door in a closed position absent tidal flooding, automatically opening and closing vents in the vent door in response to changes in ambient temperature and opening the vent door in response to sufficient pressure exerted by flood waters during tidal flooding. The automatic adjusting vents comprises the steps of: automatically sensing ambient temperature, automatically opening the vents in response to warmer ambient temperatures, and automatically closing the vents in response to cooler ambient temperatures. The method can further comprise: automatically biasing the vent door to the closed position, releasably latching the vent door in the closed position, and allowing the vent door to swing open in the direction of the tidal flow. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Presently preferred and alternative embodiments of the inventive arrangements are shown in the drawings, it being understood, however, the inventive arrangements are not limited to the precise arrangements and instrumentalities shown. 
     FIG. 1 a  is a front elevation of a door of a flood vent according to the invention. 
     FIG. 1 b  is a side elevation of the door in FIG. 1 a.    
     FIG. 2 a  is a front elevation of an outer frame of the flood vent. 
     FIG. 2 b  is a side elevation of the outer frame in FIG. 2 a.    
     FIG. 3 is a side elevation of the flood vent inserted into a wall and stakes for attaching the flood vent to the wall. 
     FIG. 4 shows the stakes of FIG. 3 inserted into the outer frame of the flood vent. 
     FIG. 5 is an expanded sectional side elevation of a stake attached to the wall. 
     FIG. 6 is an expanded partial side elevation of the stake in FIG. 4 inserted into the outer frame of the flood vent. 
     FIG. 7 is a sectional elevation of the door in FIG. 1 a.    
     FIG. 8 is a detail side elevation of a temperature sensitive actuating device. 
     FIG. 9 a  is a cross section taken along line  9 — 9  in FIG. 7 showing the louvers in a closed position. 
     FIG. 9 b  is a cross section taken along line  9 — 9  in FIG. 7 showing the louvers in an open position. 
     FIG. 10 is a front elevation of the flood vent showing the louvers in a closed position. 
     FIG. 11 a  is a cross-sectional side elevation of the flood vent showing the reaction of the float to an increasing or a decreasing water level. 
     FIG. 11 b  is a cross-sectional side elevation of the flood vent showing the door swinging open after the float has released the door. 
     FIG. 12 is a side elevation of the door and outer frame before insertion of the door into the outer frame. 
     FIG. 13 a  is a side elevation of the door and outer frame showing the positional relationship of the door to the outer frame during the insertion of the door into the outer frame. 
     FIG. 13 b  is a side elevation of the door and outer frame illustrating the positioning of the door in FIG. 13 a  to a closed position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1 and 2 illustrate the flood vent according to the preferred embodiment of an inventive arrangement. In the presently preferred embodiment, the flood vent has an outer frame  10  formed from a corrosion resistant material, preferably stainless steel. Although the outer frame is not limited as to a particular dimensioning, the dimensions of the outer frame  10  preferably vary from that of an 8″×16″ concrete masonry unit (CMU) to 16″×16″, that of two CMUs. In the presently preferred embodiment, the top rail  12  and the bottom rail  14  each are 17{fraction (11/16)}″ long, and the side rails  16  are 9{fraction (11/16)}″ long. 
     The door  22  is attached to the outer frame  10  so that the door  22  can pivot relative to the outer frame  10 . Many features capable of pivoting the door  22  relative to the outer frame  10  is are well known in the art, and all such features are acceptable for use with this invention. However, the presently preferred features to attach the door  22  to the outer frame  10  are door pins  86  extending from sides of the door  22 . The door pins  86  are adapted to be received within door slots  88  disposed within the outer frame  10 . 
     The door  22  is preferably made with a corrosion-resistant material, most preferably stainless steel. The door  22  also comprises two mesh grilles  24  disposed on opposing faces of the door  22 . Although the mesh grilles  24  will allow air and water to pass through the door  22 ; the size of the openings in the mesh grilles  24  are sufficiently small to prevent objects such as small animals or debris from passing through the door  22 . 
     Any means of securing the outer frame  10  to a wall opening is acceptable. An example of a securing means is a set of stainless steel set screws. Divots can be drilled in the masonry prior to insertion of the setting screws to ensure proper security. Also, the perimeter can be caulked as required. 
     As illustrated in FIGS. 3-6, a presently preferred means of securing the outer frame  10  to the wall opening is with stakes  11 . The stakes  11  include a forked longitudinal member  13  and an attachment portion  15 . The attachment portion  15  preferably includes a slot through which a fastener, such as a nail or screw, can be inserted into the wall  17 . The forked longitudinal member  13  preferably includes a pair of tines  19 . 
     The tines  19  are configured to be inserted into a slot  23  in the outer frame  10  in one direction but resistant to removal in the opposite direction. Any feature on the tines  19  that resists removal in an opposite direction is acceptable; however, the preferred features are teeth  21  with each tooth  21  configured with two contact surfaces  25 ,  27 . Also, the combined width of the tines  19  and teeth  21  are preferably greater than the width of the slots  23 , and the perpendicular distance between the tines  19  is at least as great as the difference between the combined width of the tines  19  and teeth  21  and the width of the slots  23 . 
     In the preferred embodiment, a first of the contact surfaces  25  is oriented at an angle relative to the direction the stake  11  is to be inserted into the slot  23 , and a second of the contact surfaces  27  is oriented substantially perpendicular to the insertion direction of the stake  11 . Pressure from inserting of the stake  11  into the slot  23  against this angled contact surface  25  forces the tines  19  towards one another and enables the stake  23  to be inserted into the slot  23 . Also, because the second contact surface  27  is oriented substantially perpendicular to the insertion direction, this contact surface  27  prevents removal of the stake  11  from the slots  23 . However, the stake  11  can be removed from the slots  23  if the tines  11  are forced together such that the combined width of the tines  19  and teeth  21  are less than the width of the slots  23 . 
     This preferred embodiment of the attachment means has serveral advantages during installation, maintenance, and removal of the flood vent  8 . During installation, the stakes  11  would preferably first be attached to the inside face of the wall  17 . Attachment of the stakes  11  to the inside face is made easier because the flood vent  8  does not yet have to be inserted into the wall  17 , which leaves an opening in the wall  17  that allows access to the inside face. Once the stakes  11  are secured, final installation only requires the flood vent  8  be slid into the opening with the stakes simultaneously being inserted into the slots  23 . 
     Once inserted into the wall  17 , the flood vent  8  is difficult to remove. However, if the flood vent  8  does have to be removed for maintenance, or any other purpose, holding the tines  19  together will enable the stakes  11  to be removed from the slots  23  and thereby allow the flood vent  8  to be removed from the wall  17 . However, because this is a difficult and nonobvious process, it would discourage removal of the flood vent  8  by unauthorized persons. 
     FIGS.  7  and  9 - 10  illustrate the equally spaced positioning of the finned louvers  58  within the door frame  28 . A vertical rod  60 , made from a corrosion-resistant, strong material, such as stainless steel, couples the finned louvers  58  to a temperature sensitive actuating device  36  (best illustrated in FIG.  8 ). The temperature sensitive actuating device  36 , so named because the device translates thermal inputs into physical motion, is adjusted to drive the finned louvers  58  open during warm temperatures and to fully close the louvers when the temperature falls below forty degrees Fahrenheit. 
     FIG. 7 illustrates a sectional view of the latching mechanism  70 . The latching mechanism  70  works by sensing the level of water passing through the flood vent  8 , and at a preset level, the latching mechanism releases the door  22 . At a time when the level of water has decreased sufficiently so that the door  22  hangs perpendicular to ground, the latching mechanism  70  is reset. Although any type of latching mechanism  70  so capable is acceptable, the presently preferred latching mechanism uses a float  72 , which indicates the level of water. Although positioned within the door  22 , the door  22  allows water to contact the float  72 . Once the float  72  is lifted by the water to a preset level, the door  22  is released. Many types of devices are capable of sensing the float  72  at a pre-set level and capable of subsequently releasing the door  22 , and the invention is not limited as to a particular type of sensing and releasing device. 
     In a preferred embodiment, the sensing and releasing device is a pin  74  extending from the float  72  which is adapted to be inserted into an open slot  78  in the outer frame  10 . As illustrated in FIG. 11 a,  when the pin  74  is positioned within the open slot  78 , the door  22  is prevented from swinging in either direction. The position of the opening of the open slot  78  determines the level of water at which the door  22  will open. Once the float  72  is lifted by water such that the pin  74  exits the opening of the open slot  78 , the pin  74  is not constrained by the open slot  78  and will tend to rotate in the direction of the current of the water as illustrated in FIG. 11 b . 
     The outer frame  10  also preferably includes a channel  80  adapted for allowing passage of the pin  74  through the outer frame  10  as the door  22  rotates back or forth. The width of the channel  80  is preferably at least as great as the range of movement of the pin  74  in the door  22 . The range of movement of the pin  74  is preferably constrained by a pin slot  82  in the door  22  through which the pin  74  extends. 
     Use of the float  72 , pin  74  and open slot  78  also acts as a resetting mechanism. When the water level drops sufficiently, the pin  74  is lower than the opening in the open slot  78  if the door  22  is at a perpendicular position relative to ground. However, the door  22  may not be perpendicular until the weight of the door  22  overcomes the force of the current of water pushing against the door  22 . Guides  84  (best shown in FIG. 2 b ) disposed on the outer frame  10  are used to position the pin  74  to the level of the opening in the open slot  78 . These guides  84  are advantageously used when the door  22  returns to perpendicular at a level of water in which the pin  74  is much lower than the opening in the open slot  78 . The guides  84  disposed on both sides of the open slot  78  are angled upward to position the pin  74  upward as the door  22  rotates to perpendicular. Upon reaching perpendicular, the pin  74  is at the level of the opening of the open slot  78 , such the when the pin  74  is positioned over the opening, the pin  74  will fall into the open slot  78  thereby resetting the latching mechanism. 
     FIGS. 12 and 13 illustrate the preferred features of the flood vent  8  for removing and inserting the door  22  into the outer frame  10 . As shown in FIG. 12, the door  22  is first inserted into the frame  10  by positioning the door pins  86  on the door  22  into an opening of a door slot  88  in the outer frame  10 . The opening of the door slot  88  is positioned slightly higher than the final vertical position of the door pins  86  so that the door  22  must be positioned at an angle relative to perpendicular to be inserted into the opening of the outer frame  10 . Once each pin  86  is in its respective door slot  88  the door pin  86  is constrained from movement in any direction except along the length of the door slot  88 . The bottom of the door slot  88  defines the final horizontal and vertical position of the door pins  86 . 
     A length of the door slot  88  adjacent the bottom of the door slot ad is preferably perpendicular relative to ground. In so doing, the door pin  86  is constrained vertically even if the door pin  86  is positioned slightly upward. Also, this feature prevents the door  22  from being removed from the outer frame  10  when the door  22  is positioned perpendicular relative to ground. Thus, to remove the door  22 , the door  22  must first be positioned at an angle other than perpendicular so that the door pins  86  can first be lifted upward in the door slot  88  and then towards the opening of the door slot  88 . 
     It should be understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application. 
     The invention can take other specific forms without departing from the spirit or essential attributes thereof for an indication of the scope of the invention.