Abstract:
A vent assembly has a base and a cover connected to the base. The cover moves between a closed and open position. A fan is optionally mounted for rotation in the base. A mechanism, including a strut system, raises and lowers the cover. The strut system is connected with the cover at two positions spaced from one another. When the cover is in its closed position, a retention force is provided by the strut system and is distributed about the cover.

Description:
FIELD 
     The present disclosure relates to vent assemblies and, more particularly, to a mechanism for raising and lowering the top cover. 
     BACKGROUND 
     In motor vehicles, such as motor coaches, that include a living area, it is desirable to have a vent assembly that enables the interior of the coach to vent to the outside. Ordinarily, a vent assembly is utilized that is capable of moving air either into or out of the interior of the motor coach. One such fan assembly is illustrated in U.S. Pat. No. 4,633,769 entitled “Roof Vent Fan Assembly”. 
     When the motor coach is being driven, it is desirable to have the cover in a down position. However, it is also possible that the cover may be raised to enable the interior to vent. The above vent assembly includes an arm to raise and lower the cover between an open and closed position. The arm is directly connected to a bracket that is coupled with the cover. 
     The disclosure provides a strut system that connects with an arm and with the cover. The strut system provides two connecting positions to retain the cover onto the base. The system provides an over center retention force to maintain the cover on the base. 
     SUMMARY 
     According to a first aspect of the disclosure, a vent assembly comprises a base that is secured in an opening in a vehicle. A cover is connected with the base. The cover is movable between an open and a closed position. Optionally, a fan is mounted for rotation within an opening in the base. A mechanism raises and lowers the cover between the open and closed position. The mechanism includes a strut system connected to the cover at two positions that are spaced from one another. When the cover is in a closed position, a force is provided by the strut system which is distributed about the cover to maintain the cover on the base. The cover includes a hinge on one side of the base. The two connections are positioned on the cover spaced away from the hinge side and on opposite sides of the fan. The strut system includes a U-shape strut coupled with a pair of brackets mounted on the cover to assist in raising and lowering the cover. The cover has a rectangular configuration with the hinge along one side and the two connection positions along the two sides perpendicular to the hinge side, both positions extending towards the opposite parallel side. The mechanism includes an arm connected with the U-shaped strut. The arm includes a pronged receptacle to receive a leg of the U-shaped strut. A pair of bearing blocks are positioned on the base to receive a web of the U-shaped strut. The bearing blocks position the U-shaped strut on the base. The connecting positions extend beyond a mid-line of the cover away from the hinged side to provide an over center force to retain the cover in the closed position. 
     According to a second aspect of the invention, a mechanism to raise and lower a cover of a vent assembly comprises an arm and a strut. The strut is connected with the cover at two positions that are spaced from one another. When the cover is in its closed position, a retention force is provided by the strut and distributed about the cover. The strut system includes a U-shaped strut to be coupled with a pair of brackets mounted on the cover. The arm includes a pronged receptacle to receive a leg of the U-shaped strut. Also, a pair of bearing blocks receive a web of the U-shaped strut to position the strut onto a base of the fan assembly. 
     According to a third aspect of the invention, a vent assembly comprises a base to be secured to an opening in a vehicle. A cover is hinged to the base. The cover has a rectangular configuration and is movable between an open and a closed position. A fan is optionally mounted for rotation in an opening in the base. A mechanism to raise and lower the cover between the open and closed position includes an arm associated with the base. The arm is coupled with a crank to initiate movement of the arm to raise and lower the arm. A strut is connected with the arm and with the cover. The strut is connected to the cover at two positions spaced from one another. When the cover is in a closed position, a retention force is provided by the strut and is distributed about the cover to retain the cover in a down position. The arm has an overall J-shape with a strut coupling mechanism at one end and a plurality of teeth at the other. The teeth are coupled with a screw mechanism of the crank to raise and lower the arm. The strut has an overall U-shape and is coupled with a pair of brackets mounted on the cover. The arm includes a pronged receptacle to receive a leg of the U-shaped strut. A pair of bearing blocks are positioned on the base to receive a web of the U-shaped strut to position the strut onto the base. 
     Further areas of applicability will become apparent from the provided description. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
         FIG. 1  is a perspective view of a vent assembly with the cover in an open position. 
         FIG. 2  is a view like  FIG. 1  with the cover in a closed position. 
         FIG. 3  is a side elevation view of the vent assembly in  FIG. 1 . 
         FIG. 4  is a cross section view of the vent assembly in the open position. 
         FIG. 5  is a side elevation view like  FIG. 3  with the cover in a closed position. 
         FIG. 6  is a cross section view of the vent assembly in the closed position. 
     
    
    
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. 
     Turning to the figures, a vent assembly is illustrated and designated with the reference numeral  10 . The vent assembly  10  includes a base  12  and a cover  14 . A hinge  16  pivotally couples the cover  14  with the base  12 . Thus, the hinge  16  is secured to the cover  14  and either the base upper portion  20  or the deck  22  of the base  12 . The base  12  includes a lower portion  24  which is positioned through an aperture in a vehicle. 
     An optional fan assembly  26 , including a blade  28  and a motor  30 , is positioned in an opening  32  in the upper portion  20  of the base  12 . When the fan assembly is not included, the vent assembly is a static vent. The fan blade  28  rotates in the opening  32  to withdraw air out of or to deliver air into the interior of the vehicle. 
     A mechanism  40  is positioned on the base  12  to raise and lower the cover  14  from the base  12 . The raising and lowering mechanism  40  includes a strut  42 , arm  44  and crank  46 . The strut  42  has an overall U-shape as illustrated in  FIG. 1 . The strut  42  includes a pair of legs  48  and  50  as well as a web  52 . Each leg includes an end  54  and  56  which projects parallel to the web  52 . The ends  54  and  56  include bushings  58  that ride in slots  60  of brackets  62 . The brackets  62  are secured to the cover  14  via fasteners. The web  52  of the strut  42  is secured into bearing blocks  64 . The bearing blocks  64  include a base  66  secured onto or integrally formed with the top portion  20  of the base  12 . The bearing block bases  66  include a channel  68  to receive the web  52  of the U-shaped strut  42 , as seen in  FIGS. 1 and 4 . Also, covers  70  are positioned over the web  52  to secure the web  52  in the bearing block bases  66  onto the base  12 . Fasteners secure the covers  70  with their respective base  66 . 
     Accordingly, the U-shaped strut provides a connection at two positions on the cover  14 . When the cover  14  is in its closed position as illustrated in  FIGS. 2 ,  5  and  6 , the ends  54 ,  56  of the U-shaped strut  42  extend beyond the mid point  72  of the fan base  12 . Also, the ends  54 ,  56  of the struts  42  are spaced from the hinge  16  towards the side of the rectangular cover  14  opposing the hinge  16 . Thus, the strut  42  applies a retention force to maintain the cover onto the base  12 . Ordinarily, a seal  74  is positioned about the periphery of the upper portion  20  so that when the cover  14  is in its down position, the seal is contacted by the cover  14  as seen in  FIG. 6 . This compresses the seal  74  to provide sealing of the cover  14  with the base  12 . By having the two point system, the force to retain the cover on the base  12  is distributed substantially equally on both sides of the cover  14 . 
     The arm  44  has an overall J-shape with a strut receiving receptacle  80  at one end and a plurality of teeth  82  at the other. The J-shaped body  84  of the arm is essentially a flat planar member. The teeth  82  are in the plane with the body  84 . The strut receiving receptacle  80  projects perpendicular to the body  84 . The receptacle  80  includes a pair of prongs  86  which receive the rod-shaped strut leg  50  of the strut  42 . 
     The tooth end of the arm body  84  includes an aperture  88  which receives a pin  90  to fix the arm  44  within the housing  92 . The housing  92  is opened at the top and includes a cylindrical portion  94  which receives a screw member  96  of the crank  46 . A handle  98  is secured to one end of the screw member  96  to enable rotation of the screw in the housing  92 . 
     The mechanism  40  lifts and lowers the cover  14  as follows. The handle  98  is rotated which, in turn, rotates the screw  96 . The screw  96 , in meshing contact with the teeth  82 , moves the cover  14  between positions. As the screw  96  rotates, the teeth  82 , move one direction or the other to open or close the cover  14 . As the teeth  82  are moved one way or the other, the body  84  pivots about the pin  90 . As this occurs, the arm receptacle  80  is moved up or down which, in turn, moves the strut  42 . As this occurs, the bushings  58  slide in the slots  60  of the brackets  62  which lift or lower the cover  14 . When the cover  14  is brought into its closed position, as illustrated in  FIGS. 5 and 6 , the ends  54  and  56  of the strut  42  are past the center line  72  of the cover  14 . This provides an over center mechanism to compress the seal  74  positioned on top of the base upper portion  20  to seal the cover  14  with the base  12 . The U-shaped strut  42  provides a downward retention force on both sides of the fan via the brackets  62 . This downward force provides a distributed force about the cover  14  to maintain the cover  14  in contact with the base  12  in a closed position. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.