Patent Application
20050086867
The present invention relates to an access door. More particularly this invention concerns a hatch or panel that is set in a ceiling or wall to allow occasional access to plumbing, wiring, or the like behind the ceiling or wall.
In construction it is frequently necessary to provide occasional access to valves, switches, punch-down blocks, and the like that are behind the wall or ceiling. Such a door typically comprises an outer frame that is permanently set in the wall and an inner frame and panel that are secured to the outer frame by hinges along one edge and a releasable latch along an opposite is edge. The access door need not be complex, as it is used infrequently, but must be unobtrusive when installed, that is typically be flush so it can be finished like the wall, and centered in its opening so it presents a nice appearance.
Thus a standard access door comprises as described in German patent 37 36 060 or EP 0,567,731 a pair of annular L-section frames, one within the other. The outer wall frame is typically set permanently in the wall, and the inner panel frame is adapted to hold a wall or ceiling panel and is releasably retained in the wall frame by some sort of hinge/latch assembly. In a typical installation the panel frame is adapted to hold one or two thicknesses of standard gypsum board, with in some instances a thin steel plate on the back face of the inset panel. The frames are formed with centering bumps that keep the inner frame at a uniform spacing withing the outer frame.
It is an object of the present invention to provide an improved access door.
Another object is the provision of such an improved access door whose center panel assembly is perfectly centered in the outer frame.
An access door has according to the invention a rectangular outer frame adapted to be set in a wall and having two longitudinal sides and two transverse sides defining four corners and a rectangular inner frame congruent to the outer frame, having longitudinal and transverse sides and four corners, and dimensioned to fit within the outer frame. Respective hinge plates fixed at corners at ends of one of the longitudinal sides of the inner frame each have an outer part bearing outward on a back face of the outer frame for holding the inner frame in the outer frame and for pivoting of the inner frame in the outer frame generally about the one longitudinal side. Each of the plates is formed with a transversely outwardly open centering notch. A latch is engaged between the inner and outer frames at a longitudinal side opposite the one longitudinal side. Respective centering tabs on the outer frame are engageable in the centering notches of the hinges.
Thus the hinges are modified to take care of at least part of the centering function. When the door is provided with a hold down plate between its hinges, according to the invention, this is done by providing inner and outer centering plates on the one longitudinal side between the hinges, one of the plates being formed with a central centering tab and the other of the plates being formed with a central centering notch in which the central tab is fitted in a closed position of the inner frame.
According to the invention, in a position of the inner frame centered in the outer frame, the centering tabs of the hinges fit with longitudinal play but with transverse abutment in the centering notches of the hinges and the central centering tab fits with transverse play but with longitudinal abutment in the central centering notch. In this manner the central structure—that is the inner frame and the panel it carries—is accurately centered at least at one of the longitudinal sides in the outer frame. Since the transverse and longitudinal centering are done by different parts, they do not have to be mounted at closely determined tolerances relative to each other.
The central centering tab has a rearwardly bent outer end according to the invention that serves for fitting the inner frame into the outer frame. In addition the hinge plates have longitudinal extensions formed with the respective notches.
According to another feature of the invention two transversely effective spring latches are provided at the other longitudinal side near ends thereof between the inner and outer frames, and two longitudinally effective spring latches are also provided at the transverse sides near the other longitudinal side between the inner and outer frames. These spring latches serve to press the inner frame into the centering formations on the outer frame and ensure perfect centering of the inner frame when fitted to the outer frame.
The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:
As seen in
More particularly, the corner hinges 4 each comprise a rigid flat leaf 5 spot welded to a back face of the back flange inner frame 2 and a coplanar and rigid flat outer leaf 6 that lies against the back face of the back flange of the outer frame 1 and is of hook shape so that the inner frame 2 has to be canted to be fitted through the outer frame 1. In addition each hinge 4 forms on the frame 2 an outwardly and transversely open notch 8 into which fits an inwardly and transversely projecting tab or tooth 9 mounted on the outer frame 1. The notches 8 each have a longitudinal width greater by a spacing SL than a longitudinal width of the respective tooth 9, but the tooth 9 has a transverse dimension T that is such that when the frame 2 is perfectly transversely centered in the frame 1, its outer end bottoms on the floor of the notch 8.
The frame 2 carries centrally between the hinges 4 a centering plate 11 formed with a central transversely outwardly open notch 10 into which fits a tab or tooth 12 carried on the outer frame. Both the notch 10 and tooth 12 are of the same longitudinal width BL so that the tooth 10 fits snugly in the notch 12 when the frame 2 is perfectly longitudinally centered in the frame 1. The tooth 12 is, however, shorter transversely by a transverse spacing ST than the depth of the notch 12. Thus transverse centering of the frame 2 is taken care of by the two tabs 9 in the notches 8 and longitudinal spacing is the job of the center tab 10 in the notch 12. The inner end of the tab 12 is bent back at 13 to facilitate fitting of the inner frame 2 into the outer frame 1.
The latches 3a and 3b are identical and mounted on angle plates 16 at the respective corners of the outer frame 1 and similar angle plates 25 fixed to the corresponding corners of the inner frame 2. These latches 3a and 3b have respective U-shaped springs 14a and 14b with bights seated in pivot eyes 17a and 17b bent outward from the respective outer plates 16 and two arms 15a and 15b that pass through guide plates 18a and 18b also bent outward from the outer plates 16 and that engage tongues 19a and 19b bent outward from the inner plates 25. The arms 15a and 15b, whose ends can be formed as eyes, bear on the respective tongues 19a and 19b so as to push them away. Thus the latches 3a spring-bias the inner frame 2 transversely toward the left as seen in
Midway between the latches 3a there is a further latch 20 comprised of a flexible strand or element 20 having its ends seated in symmetrically arranged brackets 23 fixed on the back flange of the outer frame 1 and forming a loop 21 engageable over a hook 22 provided on the back face of the back flange of the inner frame 2. The strand 20 is elastomeric so that, when engaged over the hook 22, it holds the inner frame 2 in the
The access door according to the invention is open as described in above-cited German 37 36 060 by pushing in on one or both of the corners with the latches 3a and 3b so that the door assembly formed by the frame 2 and panel 24 pops out slightly, allowing it to be pulled open wide enough to unhook the strand 20 and pivot it all the way out.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10343391.0 | Sep 2003 | DE | national |
