VIEWING AND ORAL COMMUNICATIONS ASSEMBLY FOR DOORS

Abstract: There is disclosed a viewing and oral communications assembly (22) for doors. The assembly is generally rectangular in shape, having mirror surfaces (52) to transmit images from positions adjacent to the door through the assembly and having audio communication slots which are closed by expansion of intumescent material (68) in the presence of heat.

Description: The present invention relates to a device which allows a person to look and, in preferred embodiments of the invention, to speak through a door without opening the door. The device is intended to be used for identifying, and communicating with, a caller outside the door without opening it. Numerous devices have long been used for this purpose, including various small hinged or sliding doors mounted on the door selectively to obstruct or clear a small opening through the door. Such devices are normally positioned at approximately adult-eye level. Other widely used devices include "fish-eye" lens devices mounted in holes in the door, also at eye level, but such devices do not facilitate oral communication through the door. Conventional peephole devices typically permit viewing of an area generally opposite the peephole but make it difficult or impossible to see areas close to the door and not directly in front of the peephole, thereby enabling someone to crouch below or to one side of the peephole against the door or building out of sight of a person looking through the peephole. Furthermore, while such conventional openings permit oral communication through the door, they also typically transmit smoke and heat from a fire and permit transmission of harmful materials by a would-be intruder. "Fish-eye" lens devices provide a wider viewing angle through the door but significantly distort the image and do not provide for oral communication through the door. Conventional "fish-eye" lens devices also frequently transmit heat from one side of the door to the other and may thus reduce the fire rating of a door in which they are mounted. This may be an important concern because many doors, on which the use of viewing devices is desirable, must be fire rated. Accordingly, the use in such doors of a viewing device which reduces the fire rating is not acceptable. Typical prior art devices for identifying a caller on the other side of a door include the "Attachment For Doors" described in U.S. Patent No. 1,901,303 to H.F. Keil, the "Door For Panels" described in U.S. Patent No. 1,799,164 to S.E. Griswold, the "Vandal Resistant Security View Port" described in U.S. Patent No. 4,571,901 to Morris and Hafner, the "Wide-Angle Spy Glass" described in U.S. Patent No. 4,116,529 to Yamaguchi and the "Wide Angle Door Viewer" described in U.S. Patent No. 4,251,127 to Yamaguchi. In addition DE-C-263 483 discloses a viewing assembly which, in one embodiment, has a piece of transparent material held in a frame, and includes mirrors located to reflect images through the transparent material. According to the present invention, there is provided a viewing assembly comprising a piece of transparent material held between first and second retaining means located respectively on first and second sides of the transparent material; and at least one mirror located so as to to reflect images through the transparent material from positions on the first side of the transparent material, characterised in that said viewing assembly includes a convoluted audio path from one side of the transparent material to the other, and in that the transparent material is provided with a coating limiting the transmission of light from the second side of the transparent material to the first. The assembly is primarily intended for location in a door of a room or building, to enable a person within the room or building to identify a person on the other side of the door. However, it may be used in other locations, such as in a door or a side of a security vehicle, or in doors of prison cells, to enable a warder to see inside a cell. The assembly according to the present invention is intended for location at adult-eye level, approximately 1.5m (5 feet) above floor level through the horizontal centre line of the device. In preferred embodiments of the invention, interior and exterior frame assemblies hold a rectangular piece of high-temperature glass in place in a frame. Preferably, the transparent material is held in a frame which does not make continuous contact with the edge of the transparent material and which, together with the first and second retaining means and the piece of transparent material, defines the convoluted audio path through the viewing assembly to facilitate oral communication; however, intumescent material on the frame adjacent the transparent material edge, and elsewhere, swells when heated in order to seal against the edge and prevent transmission of smoke or flame during a fire. Angled mirror surfaces are preferably positioned at either side and along the top of the assembly on its exterior side, such that, when the assembly is positioned in an exterior door of a building, they reflect images from positions immediately adjacent the door and building at the sides and below the assembly, thereby permitting a person inside the door to see anyone crouching below or to one side of the viewing assembly. The transparent material is preferably glass. Alternative closures, such as a hinged flap and sliding shutters, on the inside of the assembly may be provided to close the viewing path when the assembly is not in use and permit selective opening of the viewing path. The hinged flap may be provided with a sloping slot to make it possible to look through the slot when the flap is partially lifted. The inner ends of sliding shutters may be V-shaped, and one end may overlie the other so that a diamond-shaped aperture results when the shutters are partially opened. When installed in fire rated doors, preferred embodiments of the viewing assembly according to the invention may be provided without any direct heat transmitting contact between the inside and the outside, thereby reducing degradation of door fire rating which might otherwise result from installation of such a device in an opening through the door. The assembly according to the invention may be provided in an exterior door or a passage door, such as a residence, apartment, hotel room or other door. The disclosed structure provides a very wide angle of clear, undistorted vision in all directions (except upwards), together with the facility for oral communications through the door. For a better understanding of the present invention, and to show how the same may be brought into effect, reference will now be made, by way of example, to the accompanying drawings, in which:- FIG. 1 is a perspective view of the outside of a typical exterior or passage door in which the viewing and oral communications assembly of the present invention is mounted; FIG. 2 is a section taken along lines 2-2 in FIG. 1 showing a horizontal cross section of the assembly of the present invention and a portion of the door in which it is mounted; FIG. 3 is a section taken along lines 3-3 in FIG. 2; FIG. 4 is an enlarged fragmentary section taken along lines 4-4 in FIG. 2 showing the audio communication passage in the assembly according to one embodiment of the present invention; FIG. 5 is an exploded perspective view of the assembly taken from the interior side of the assembly; FIG. 6 is a perspective view of the inner side of an alternative embodiment of the present invention having sliding covers; FIG. 7 is a fragmentary section taken along lines 7-7 in Fig. 6; and FIG. 8 is a perspective view of the outer side of a viewing assembly of the present invention having a bezel cover with room numbers. FIG. 1 illustrates the outside of a typical exterior or passage door 20 in which the viewing and oral communications assembly 22 of the present invention is mounted at approximately adult-eye level, typically at approximately 1.5m (5 feet) above floor level. As will be appreciated by reference to FIGS. 2 and 5, the assembly comprises generally a rectangular piece of glass 24 which is captured in a non-combustible frame formed by two generally U-shaped frame members 26. Frame members 26 capture glass 24 in slots 28 centered in the ends 30 of frame member 26. The slots stop short of the plate 32 which connects the ends 30, thereby providing passages around glass 24 to facilitate passage of sound and thus permit oral communications through the assembly 22. The interior and exterior frame assemblies 26 are preferably formed of non-combustible fiber board, such as "Monolux 500" (Trade Mark) available from Cape Boards and Panels, Ltd., of Iver Lane, Uxbridge UB8 2JQ, England. Glass 24 may be Pilkington's Georgian Wire (Trade Mark) glass, available from Pilkington Glass, Ltd., of Prescot Road, St. Helens, Merseyside WA10 3TT, England, which is self supporting at temperatures of up to 900°C, and may be coated with or bonded to a film 34 to limit transmission of light from the inside of assembly 22 to the outside. Film 34 may, for instance, be Banafix 15 (Trade Mark) film available from Banafix, Ltd., of Banafix House, Amersham Road, Chesham, Bucks HPS 1NF, England. Alternatively, a suitable film may be sprayed on to the glass. Frame members 26 are held in a position generally centered within a rectangular opening 36 in door 20 by first and second retaining means, in the form of an outer bezel 38 and an inner bezel 40, each of which form a rectangular frame around opening 36 and extend into that opening to overlie frame members 26 adjacent to glass 24. Importantly, bezels 38 and 40 do not touch glass 24, as is particularly well illustrated in FIG. 4, which shows a space between bezel bottom 51 and glass 24 and between inner bezel side 42 and glass 24. This permits passage of sound above and below glass 24, as explained above. As may be seen by reference to FIGS. 2 and 5, inner bezel 40 includes inwardly extending sides 42 which extend from the frame portion 44 of inner bezel 40 at substantially a right angle. As is best shown in FIG. 4, the edges of sides 42 adjacent to glass 24 may be provided with a thickened region or lip 43 in order to create a longer and more convoluted path around the edge 71 of glass 24. Such a lip 43 is intended to deflect and impede passage through viewing assembly 22 of any toxic or otherwise harmful sprays which may be directed through assembly 22 from the outside. Outer bezel 38 includes a similar bezel frame 46 and a outer bezel box 48 which extends into door 20 opening 36 and has a generally rectangular exterior to lie against the outer margin of frame members 26. The generally vertical inside surfaces 50 of bezel box 48 form an acute angle with each of the surfaces of glass 24 and outer bezel bottom 51. A mirror 52 is mounted on each vertical surface 50. Such generally vertical mirrors 52 reflect images to a viewer inside the door 20 from areas immediately adjacent the outside of the door 20 at the sides of assembly 22 and to some extent below it. The generally horizontal top inside surface 55 of bezel box 48 is formed by a downwardly sloping canopy portion 57 of outer bezel 38 so that top inside surface 55 also forms an acute angle with the surface of glass 24. A mirror 53 is mounted on top inside surface 55 to provide additional reflected images from the area adjacent the door 20 and immediately below the viewing assembly 22. Mirrors 52 and 53 may be provided in any number of conventional ways, as, for instance, by appropriately mounting sections of glass having either front surface or rear surface mirrors. Alternatively, highly polished metal or an appropriately metallized plastic or another material may be used, as will be readily apparent to one skilled in the art. Enlarged viewing areas may be achieved, with some concomitant distortion, by forming mirrors 52 and 53 in a convex curved shape. Assembly 22 may be mounted within door 20 by either of two alternative mounting methods. In an embodiment of the present invention intended for use in non-fire doors and illustrated on the right side of FIGS. 2 and 5, a machine screw 56 extends between inside bezel 40 and outer bezel 38 as is explained below. Alternatively, in a fire door embodiment of assembly 22, as illustrated on the left side of FIGS. 2 and 5, wood screws 62 separately fix inner and outer bezels 40 and 38 to door 20. In mounting the first embodiment of assembly 22 in non-fire rated doors, a machine screw 56 passes through a hole 58 in inner bezel 40 and into a threaded opening 60 in a boss 54 on outer bezel 38. While this mounting method results in there being no removable fasteners on the outside of door 20, the machine screw connection between inner and outer bezels 38 and 40 permits possible heat transmission between the two bezels along machine screw 56. Accordingly, the alternative mounting method, which is specifically designed for installation in fire rated doors, utilizes two wood screws 62 which pass through appropriate holes 64 and 66 in inner bezel 40 and outer bezel 38, respectively, and into the wood or other material of which door 20 is formed. Because, as indicated above, frame 26 is made of non-combustible fiber board or other appropriate non-flammable material which does not transmit heat well, mounting of assembly 22 in accordance with the second mounting method results in an assembly which transmits very little heat from one side to the other and thereby results in minimal degradation of the fire rating of the door in which it is installed. If the assembly is intended to be used in a door whose fire rating is of minor importance, for example when the first mounting method is used, it is not necessary to use a frame as described above and as shown in the drawings. Instead, it may be preferable to replace the frame by, for example, rubber extrusions into which the glass 24 can be clipped. Intumescent paint 68 is shown in FIGS. 3, 4 and 5 applied to plates 32 of the frame members 26 adjacent the longer edges 71 of glass 24, and it may also be applied elsewhere. Such intumescent material reacts to heat by swelling, and thus, in the illustrated embodiment, it seals between frame members 26 and adjacent edges 71 of glass 24 to prevent smoke and/or flame from passing through assembly 22 in the event of fire adjacent either side of assembly 22. A suitable intumescent material is Lorient LC000l available from Lorient Poly Products, Ltd., of Fairfax Road, Heathfield Industrial Estate, Newton Abbott, Devon, England. The heads of screws 62 are covered by coverplates 70 which may be glued in place or held by a wide variety of other appropriate means, such as pins protruding from the plates which engage openings in the bezel 38 and cannot be disengaged without damaging the plates 70, thus providing security by making it difficult to access the screws necessary to remove the outer bezel 38. Other methods of assembly include decorative brads or rivets, tamper-resistant screws, and use of a peripheral lip on the bezel 38 to capture the edge of plates 70 which would snap into place by being forced beyond the lip. Cover plates 70 may carry room numbers 77 (shown in FIGS. 1 and 8) or other identifying information. This may also be accomplished by substituting an outer bezel cover 79 (FIG. 8) for plates 70. Such a bezel cover 79 may be generally rectangular in shape with an opening 72 so that the cover 79 can overlie outer bezel 38 or a portion of outer bezel 38 and provide surfaces 73 adjacent the sight path through the viewing assembly 22 to carry room numbers 77, names, or other identifying information. If desired, such a bezel cover 79 may be locked in place by bezel 38 when bezel 38 is mounted on the door 20, or may be fastened to the assembly 22 by any other means, including the methods described above for fixing coverplates 70 to bezel 38. The heads of screws 56 and 62 on inner bezel 40 are covered by disc 80 which may be glued or held by other appropriate means thus providing security by making it difficult to access the screws necessary to remove the inner bezel 40. A closure may be desirable on the inside of assembly 22 to obstruct the sight and audio path provided by assembly 22. Two alternative such closures are illustrated in FIGS. 2, 3, 5, 6 and 7. FIGS. 2, 3 and 5 illustrate a hinged flap closure 74 which is a rectangular flap substantially equal in size to the face of inner bezel 40. Flap 74 is hinged along its top edge so that it may be lifted to look and speak through assembly 22 and when released will fall closed to overlie inner bezel 40. In the illustrated embodiment, the flap 74 contains a narrow horizontal slot 75 which passes through flap 74 at an angle sloping up from the outside to the inside of flap 74. Consequently, it is not possible to see through the slot 75 when flap 74 is fully closed, but when flap 74 is raised slightly, it is possible to see through slot 75 before flap 74 is raised to its fully open position. A decorative cover or finish on flap 74 may coordinate with room finish to enhance the appearance of assembly 22 or make it less obtrusive. An alternative closure is illustrated in FIGS. 6 and 7 on an alternative embodiment of the present invention, viewing assembly 22'. This closure is provided by one or more horizontally sliding shutters 76. Two such shutters 76 are illustrated in FIG. 6 with V-shaped ends 78, one of which overlies the other when shutters 76 are closed, thereby fully occluding the sight path in assembly 22′. Partial opening of shutters 76 results in a small peephole, and further movement of shutters 76 fully clears the sight and audio path of assembly 22′.

Claims: A viewing assembly comprising: a piece of transparent material (24) held between first and second retaining means (38,40) located respectively on first and second sides of the transparent material; and at least one mirror (52,53) located so as to reflect images through the transparent material from positions on the first side of the transparent material; characterised in that said viewing assembly includes a convoluted audio path from one side of the transparent material to the other; and in that the transparent material (24) is provided with a coating (34) limiting the transmission of light from the second side of the transparent material to the first. A viewing assembly as claimed in claim 1, wherein said piece of transparent material is held in a frame (26) which does not make continuous contact with the edge of the transparent material and which, together with the first and second retaining means and the piece of transparent material, defines the convoluted audio path. A viewing assembly as claimed in claim 1 or 2, further comprising intumescent material (68) in the proximity of the audio path, the intumescent material reacting to heat by swelling and sealing the audio path. A viewing assembly as claimed in any preceding claim, comprising two mirror surfaces (52) oriented generally vertically on either side of the viewing assembly and at an acute angle to the surface of the transparent material. A viewing assembly as claimed in any preceding claim, comprising a mirror surface (53) located along the top of the viewing assembly and at an acute angle to the surface of the transparent material. A viewing assembly as claimed in claim 4 or 5, wherein the or each mirror surface is convex. A viewing assembly as claimed in any preceding claim, further comprising a closure (74,76) attached to the second retaining means for selectively occluding the sight path through the transparent material. A viewing assembly as claimed in claim 7, wherein said closure is a hinged flap (74) containing a slot (75). A viewing assembly as claimed in claim 7, wherein the closure is a two-part shutter (76) with V-shaped ends (78), one of which overlies the other when the shutter is closed and which together define a diamond-shaped aperture when the shutter is partially open. A viewing assembly as claimed in any preceding claim, further comprising means (62) for independently affixing the retaining means to a door (20), thereby avoiding an efficient heat transmission path from one retaining means to the other.

Inventors: RITCHIE, RICHARD RUBEN
Applicants: RITCHIE, RICHARD RUBEN
Application year: 1988
Main classification: E06B7
IPC codes: E06B7