Abstract:
A soffit vent preventing an ingress of air while facilitating egress thereof, including a cylindrical frame containing an internal vent mechanism, which frame is mounted to the external surface of the soffit duct opening. The other end of the soffit vent is mounted on the vent duct. Within the cylindrical frame is an internal vent mechanism, comprising a cross beam defining two interstices, each interstice having a vent flap on the downstream side. A tension means holds the flaps closed, until the pressure within the building is greater than that outdoors, which pressure pushes the flaps open.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates generally to venting and specifically to controlled venting from a soffit. 
       BACKGROUND OF THE INVENTION 
       [0002]    Vents are required in buildings to permit air exchange with the outside for dryers, bathroom and kitchen fans, and heating and cooling, among other reasons. A convenient location for a vent exhaust is a soffit, which is often convenient for upstairs bathrooms, a laundry room on a higher floor, and HVAC systems in the attic. 
         [0003]    Some attempts to address this problem have been made in the prior art, for example, Canadian Patent No. 2,577,154, which describes a one-way soffit vent with an upstream valve seat and a downstream vented cover having a boss and a valve disk mounted on the boss and biased against the valve seat. This is one way to provide a valve for one-way operation, however, the valve disk is pushed against the valve seat by means of a spring. The spring may eventually weaken in its force and the soffit vent would leak, permitting air to flow back into the vent. 
         [0004]    Another attempt to solve this problem involves the use of roof vents such as described under U.S. Pat. No. 6,293,682. However, this product is installed on the roof and does not allow for it to be installed on a soffit and its installation on a roof can create weak spots in the roofing tile which allows for water to enter under the roofing tile and cause damage to the roof of a building. In addition, a flap is installed and relies on gravity to close. Such an application would then not be applicable in a soffit as it would remain open at all times. 
         [0005]    Therefore there is a need for an alternative soffit vent valve that does not weaken and leak air back into the vent and less complex which increases its reliability and longevity. 
       SUMMARY OF THE INVENTION 
       [0006]    Embodiments of the present invention include a soffit vent preventing an ingress of while facilitating egress from, for example, a soffit duct connected to bathroom fan. The soffit vent consists of a cylindrical frame containing an internal vent mechanism, which frame is mounted to the external surface of the soffit duct opening by means of a grill. A collar at the other end of the soffit vent is mounted on the vent duct. Within the cylindrical frame is an internal vent mechanism, comprising a cross beam mounted across the cylindrical opening within the frame, thereby defining two interstices. Each interstice has a semicircular vent flap on the downstream side. A tension means extending across the crossbeam, each end of the tension means mounted to one of the flaps, holds the flaps closed, until the pressure within the building is greater than that outdoors, which pressure pushes the flaps open. The flaps stay open so long as the pressure within the building is greater than the exterior, and once this ceases, the flaps are motivated to close by the tension means. The flaps do not pass through the interstices due to a lip around the interstice, which makes the circumference slightly smaller than that of the flap. 
         [0007]    A soffit vent for mounting on a duct opening in a soffit includes a frame; a crossbeam affixed within the frame, bisecting the frame forming first and second interstices between the frame and the crossbeam; a first vent flap pivotally connected to the crossbeam to allow for the closure of the first interstice; a second vent flap pivotally connected to the crossbeam to allow for the closure of the second interstice; a tension means; and a grill adapted to be secured to the frame. The tension means is connected from the first vent flap across the crossbeam to the second vent flap, such that it provides a force pulling the first vent flap to close the first interstice and pulling the second vent flap to close the second interstice. The frame may be cylindrical and the crossbeam may be positioned diametrically across the frame, and the first and second vent flaps may be semicircular in shape. The first interstice has a lip against which the first vent flap may rest when closed, and the second interstice may have a lip against which the second vent flap rests when closed. A collar may permit engagement with a smaller diameter vent duct. The collar may have tabs to allow for the securing of vent ducts onto the frame. The tension means may be an elastic band or a spring. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    It will now be convenient to describe the invention with particular reference to one embodiment of the present invention. It will be appreciated that the diagrams relate to one embodiment of the present invention only and are not to be taken as limiting the invention. 
           [0009]      FIG. 1  is a rear perspective view of a soffit vent, according to one embodiment of the present invention; 
           [0010]      FIG. 2  is a front view of a soffit vent, according to one embodiment of the present invention; 
           [0011]      FIG. 3  is a rear view of a soffit vent, according to one embodiment of the present invention; 
           [0012]      FIG. 4  is a detailed view of a vent frame as found in a soffit vent, according to one embodiment of the present invention; 
           [0013]      FIG. 5  is a side cut-away view of a soffit vent, in a resting position, according to one embodiment of the present invention; and 
           [0014]      FIG. 6  is a side cut-away view of a soffit vent, in an operational position, according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. 
         [0016]    With reference to  FIG. 1  and according to one embodiment of the present invention, the soffit vent consists of a cylindrical frame  10 , which contains an internal vent mechanism which controls the airflow (described in detail below), permitting air to flow out when the vent fan inside the building is operating but preventing airflow when the fan is not operating. External to the frame  10  is affixed, on the downstream side, the soffit grill  20 , and on the upstream side, a removable collar  30 , both by fastening means  40 , such as screws. The collar  30  is connected with the vent duct (not shown) by means of the angled tabs  50  present around the circumference of the adapter  60 . The collar  30  permits adaptation to a smaller-diameter section (typically  4 ″) of vent duct, or may be removed such that the soffit vent may fit a larger-diameter section (typically  6 ″) of vent duct at vent collar  70  on tabs  55 . The soffit vent is affixed to a soffit (not shown) by means of a number of screws (not shown), which would be fastened through the screw bosses  80  positioned around the soffit grill  20 . 
         [0017]    With reference to  FIG. 2 , a front (downstream) view of the soffit grill  20  and bosses  80  is shown wherein air may exit through the grill  20  via openings  25 . With reference to  FIG. 3 , a rear (upstream) view of the soffit vent is shown, showing the bosses  80 , angled tabs  50  and  55  and the rear view of the vent mechanism (detailed below). Air exits from semicircular interstice  120  and  130  which is separated with a cross beam  100  when the vent flaps (removed for clarity) are in an open position as further described below. 
         [0018]    With reference to  FIG. 4 , the vent frame  10  is shown without the vent flaps and vent mechanism. The crossbeam  100  is affixed within the frame  10 , bisecting the frame  10 ′s cross-section. A first semicircular interstice  120  and a second semicircular interstice  130  are thus formed on either side of the crossbeam  100  and frame  10 . A peripherally-protruding first lip  110  runs along the inside edge defining the first interstice  120  and a similar peripherally-protruding second lip  115  runs along the inside edge defining the second interstice  130 . Lips  110 ,  115  reduces the size of the interstices  120 ,  130  to a smaller size than the vent flaps (not shown), preventing the vent flaps (not shown) from passing through the corresponding interstices  120 ,  130 . At the midpoint of the crossbeam  100  is a saddle  140 . The crossbeam  100  is made more rigid by a reinforcement member  150 , which in the present embodiment is made of plastic and molded into the plastic of the crossbeam  100 . 
         [0019]    With reference to  FIGS. 5 and 6 , the vent mechanism consists of a first semicircular vent flap  200  and a second semicircular vent flap  210 , and a tension means  220  which rests in the saddle  140  and is affixed to the first vent flap  200  by means of a first attachment projection  170  mounted on the vent flap  200 , to the second vent flap  210  by means of a second attachment projection  180  mounted on the vent flap  210 . 
         [0020]    In a resting position, shown in  FIG. 5 , the first vent flap  200  rests against the downstream side of the first lip  110  around the first interstice  120 , closing the interstice. Similarly, the second vent flap  210  rests against the second lip  115  around the second interstice  130 , closing the interstice. The first vent flap  200  is pivotally connected to the downstream side of the crossbeam  100  by means of a first hinge  230 , and similarly the second vent flap  210  is pivotally connected to the downstream side of the crossbeam  100  by means of a second hinge  240 . The tension means  220  resting in the saddle  140  provides a motivating force for the first and second vent flaps  200 ,  210  to close the first and second interstice  120 ,  130 , respectively. 
         [0021]    A person skilled in the art would know that the tension means may be composed of rubber, as an elastic band, or a spring, or any number of other tension-providing mechanisms known in the art, while remaining within the scope of the invention. Such a person would also appreciate that the frame, and corresponding componentry, and without limitation the interstices and vent flaps, may be square or rectangular in cross-section and still fall within the scope of the present invention. Furthermore, the soffit vent is manufactured of molded plastic, however one skilled in the art would appreciate that it may be made of other materials as well and still fall within the scope of the invention. 
         [0022]    By means of the drawing of the soffit vent shown in an operational position in  FIG. 6 , the operation of the vent may be described. The vent fan (not shown) inside the building is operational and is creating pressure within the vent duct (not shown), and the first and second vent flaps  200 ,  210  are pushed away from their corresponding interstices  120 ,  130 , permitting airflow through the soffit vent. The first and second vent flaps  200 ,  210  pivot on the first and second hinges  230 ,  240  respectively, in a downstream direction from the first interstice  120  and second interstice  130 . In other words, the vent flaps  200 ,  210  open in a downstream direction in response to the pressure of the air driven by the exhaust fan. The pressure exerted by the exhaust fan (not shown) is sufficient to resist the closing force provided by the tension means  220 , which lengthens in response to the air pressure to permit the pivoting action. Once the exhaust fan ceases to operate, and the downstream air pressure is reduced, the elastic  220  motivates the vent flaps  200 ,  210  to close the interstices  120 ,  130 , by pushing against the interstice lips  110 ,  115  respectively. If a reverse air pressure situation arises, where the pressure on the downstream side of the soffit vent is greater than that on the upstream side, the pressure will only serve to seat all the more firmly the vent flaps  200 ,  210  against the lips  110 ,  115  of the interstices  120 ,  130 . 
         [0023]    Many modifications and other embodiments of the invention will come to the mind of a person skilled in the art having the benefit of the teachings presented in the foregoing description and associated drawings. Therefore, it is understood that the invention is not to be limited to the specific embodiment disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims.