Background of the Invention
This invention relates to a switchboard cabinet comprising a box-like cabinet body with an opening, a door which closes the opening of the cabinet body, and a door frame mounted in the cabinet opening and attached to the inner panels of the cabinet body, so that when the door is closed, a portion of the door frame bears against a sealing element located on the inside of the cabinet door, and the door is further provided with a flange which extends around its perimeter at a right angle to the surface of the door.
Good sealing is not usually obtained with known switchboard cabinet designs of this type, especially in the area between the door and the cabinet body, particularly when the switchboard cabinet is installed outdoors. The joint between the upper horizontal edge of the door and the cabinet body is a critical area, since rain water, for example, may collect there and enter the switchboard cabinet when the door is opened.
Summary of the Invention
A purpose of the present invention is to provide improved sealing for switchboard cabinets of the type referred to above, so that such cabinets may be installed outdoors, and the risk of rain water entering the cabinet body is diminished.
This objective is accomplished according to the present invention by the perimeter of the door being inset by providing, at least along the upper horizontal edge of the door, an extension extending beyond the outer portion of the cabinet body, so that the door frame with its vertical side members, forms a recess open toward the front of the cabinet body. A cover strip is attached to the cabinet body with the door frame, the cover strip projecting above and beyond the door when it is closed and has a sealing lip provided on the side of the cover strip facing the door, the lip bearing on the outer edge of the closed door facing it.
The cover strip covers the joint between the cabinet body and the door to insure that no water enters the cabinet body, and the sealing lip provides a means of positively sealing the area of the joint. In many cases, it is sufficient if the cover strip is provided only along the upper horizontal edge of the cabinet body. However, if complete sealing is to be achieved, then both vertical sides and the lower horizontal edge of the cabinet body should also be provided with a cover strip of this type to protect the entire joint between the door and cabinet body. When the cabinet door is closed, the sealing lip repels any water which may collect opposite it along the leading edge of the cabinet door, thus effectively preventing such water from entering the joint between the door and the cabinet body protected by the cover strip.
The cover strip is attached to the cabinet body by means of an arrangement wherein the cover strip and the door frame are bonded to the inside wall of the cabinet body, a recess formed between the cabinet body and the door frame being filled with bonding agent, and an attachment portion of the cover strip being imbedded in the bonding agent. This type of connection is particularly suitable in an embodiment wherein the cabinet body, the door frame and the cabinet door all comprise molded plastic components.
To prevent water from collecting in the joint between the cabinet body and the cover strip, in a further embodiment of the present invention, the upper surface of the cover strip is fitted flush with the outer edge of the cabinet body facing it.
In one embodiment of the present invention, both upper and lower sides of the cover strip are provided with intermediate shoulders acting as stops which bear on the front edges of the cabinet body and the door frame which delimit the recess in which the cover strip is attached, whereby the intermediate shoulders serve to limit the depth to which the cover strip can penetrate the recess; however, sufficient space remains in the recess to accommodate the bonding agent in which the narrower attachment portion of the cover strip is fully imbedded and assure that the door frame is sufficiently firmly attached to the cabinet body. In addition, a further advantageous feature is that the vertical side members of the door frame which delimit the door recess, on the side remote from the door, have a flange extending at a right angle to the door, and this flange serves to delimit the width of the recess at the end of the groove.
In a simplified embodiment of the design, the sealing lip and the cover strip may be molded in one piece.
If a cover strip of rigid material is preferred, in another embodiment of the present invention, the sealing lip may comprise a separate component with a projection fitted in a groove in the cover strip, whereby the sealing lip is fastened in this groove. The sealing lip constitutes a separate component in this version of the design and may be constructed from a material providing sufficient resiliency.
A feature to ensure that rain water runs off the cabinet is provided in a further embodiment, wherein a continuous drip flange is provided along the outer edge of the cover strip facing the cabinet door, and the sides of the cabinet body may be at an angle to the door opening which is slightly less than a right angle.
As far as the configuration of the door frame is concerned, the frame sealing member is connected to the side member of the door frame which delimits the opening by a connecting member adjacent and at a right angle to them, and the sealing element on the inside of the door is provided between two retaining members to provide space for a recess to accommodate the frame sealing member and also to maintain the retaining members spaced from the inner panels of the cabinet.
In order to maintain the joint between the cabinet body and the closed door as tight as possible, in one embodiment of the invention, the retaining member nearer the joint is shorter than the retaining member more remote from it.
Brief Description of the Drawings
The invention will now be described in greater detail with reference to embodiments shown in the accompanying drawings, wherein:
FIG. 1 shows a partial cross section of the upper horizontal edge of a known switchbox cabinet design, showing the area of the joint between the door and the cabinet body when the door is closed;
FIG. 2 shows a partial cross section corresponding to FIG. 1 with a cover strip having an integrally molded sealing lip attached to the cabinet according to this invention; and
FIG. 3 shows a partial cross section corresponding to FIG. 2, wherein a sealing lip comprising a separate component is fastened in the cover strip .
Description of the Preferred Embodiments
The drawings show only part of an upper panel of cabinet body 20, which may comprise a box-like form of molded plastic. The outer surface of the panel is designated 21. Door frame 22 is bonded in place in the front opening of cabinet body 20, as shown by the presence of bonding agent 27 in recess 26. Recess 26 is defined by a vertical side member, a lateral side member of door frame 22 and the inner panel of cabinet body 20, whereby the width at the inner portion of groove-shaped recess 26 is delimited by vertical side member 24 at a right angle to lateral side member 23. Connecting member 25 of door frame 22 extends to frame sealing member 39 which is displaced a distance from the inner panel of the cabinet body 20 and projects into the recess formed by cabinet body 20. Cabinet door 10 has perimeter flange 11 extending around its perimeter roughly at a right angle to the surface of door 10. In addition, on the inside of door 10, two retaining members 12 and 13 of different lengths are provided, between which sealing element 14 is maintained in position, whereby frame sealing member 39 of door frame 22 is compressed against sealing element 14 when cabinet door 10 is closed. Door frame 22 may comprise a one-piece frame section or may comprise four hollow sections mounted together.
It will be obvious that when a cabinet of the prior art design, as shown in FIG. 1, is installed outdoors, rain water, snow, etc., will collect on frame sealing member 39 and penetrate between cabinet body 20 and door 10.
To prevent water leakage, cover strip 30 is provided according to the present invention. As shown in FIG. 2, opposite the portion of cabinet 20 on which cover strip 30 is mounted, perimeter flange 11 of cabinet door 10 is set back from cabinet side member 20 far enough to allow access to recess 26 from the front. Attachment portion 31 of cover strip 30 is inserted into recess 26 beyond a point where section 32 narrows. Narrow section 32 is imbedded in bonding agent 27 so that cover strip 30 is attached to door frame 22 and to the inner panel of cabinet body 20. Shoulders 34 and 35 on cover strip 30 limit the extent to which attachment portion 31 can penetrate recess 26, since they bear against the edges of cabinet body 20 and lateral side member 23 of door frame 22. Just as with known designs, frame sealing member 39 insures sealing fit with sealing element 14. Cover strip 30 projects over cabinet door 10 when it is closed and sealing lip 36 bears on perimeter flange 11 of cabinet door 10 opposite it. In the embodiment illustrated in FIG. 2, sealing lip 36 is formed on the lower side of cover strip 30 facing cabinet door 10. Outer surface 33 of cover strip 30 is flush with outer surface 21 of cabinet body 20 and the cover strip may be bent downward slightly to form less than a right angle to the opening of cabinet body 20. Continuous drip flange 38 is formed on the extending side of cover strip 30 facing cabinet door 10, to improve water run-off from cover strip 30.
In the embodiment illustrated in FIG. 3, sealing lip 36 is formed as a separate element maintained in place by a projection of the sealing lip element inserted in groove 37 in cover strip 30. In this case, sealing lip 36 has the same function as previously described, but as a separate element it may be of a different material, such as one that is more resilient than the material of cover strip 30.
When cabinet door 10 is closed, sealing lip 36 seals against perimeter flange 11 of cabinet door 10 opposite it, so that even when door 10 is closed, no water collects on it.
As door frame 22 extends around the opening of cabinet body 20, only the upper horizontal edge of cabinet body 20 may be provided with cover strip 30, or alternatively, three or all four sides of the cabinet may be provided with cover strips, which may in this case be completed by, or assembled in the form of a partial or complete framework.