GB2291680A

GB2291680A - Letter plate assembly

Info

Publication number: GB2291680A
Application number: GB9515051A
Authority: GB
Inventors: Richard Harvey
Original assignee: Paddock Fabrications Ltd
Current assignee: Paddock Fabrications Ltd
Priority date: 1994-07-22
Filing date: 1995-07-24
Publication date: 1996-01-31
Anticipated expiration: 2015-07-24
Also published as: GB2291680B; GB9515051D0

Abstract

A letter plate assembly comprises a metal frame 10 having a closure flap 14 pivotally mounted thereto by means of at least one metal pivot pin. A plastics moulding 44 is associated with the frame 10, the plastics moulding 44 including a tubular region 46 arranged to extend within an opening of a door, and carrying a seal 52 arranged to encircle the tubular region 46, the seal 52 being arranged to contact the flap 14 when the flap 14 is in a closed position, in use. The assembly can be used with a second identical metal frame 12 carrying a respective closure flap 14 pivotally mounted thereto by means of metal pivot pins. Respective telescopic tubular members 46, 60 are provided for the metal frames 10, 12. <IMAGE>

Description

LETTER PLATE ASSEMBLY This invention relates to a letter plate assembly of the type comprising an outer pivotally mounted flap for closing the outer end of an aperture in a door.

A known letter plate assembly comprises outer and inner plastics mouldings for positioning in alignment on the outer and inner faces respectively of a door, each moulding pivotally mounting a closure flap, and the plastics mouldings including regions telescopically slidable within one another within the door. The flaps are pivotally mounted on their respective plastics moulding by means of plastics pivots. Where such letter plates are used on heavy doors where the only door furniture present is the letter plate, there is a tendency for the door to be pulled shut or open using the letter plate. The above described letter plate has the disadvantage that when subject to such forces, there is a tendency for the pivot arrangement to fail.

A further known type of letter plate assembly comprises outer and inner aluminium frames carrying flaps pivotally mounted thereto by means of metal pivots. Such letter plates have the disadvantage that weather proofing of the assembly by including seals and/or draught excluding brushes is difficult.

According to a first aspect of the invention there is provided a letter plate assembly comprising a first metal frame, a closure flap pivotally mounted upon the first frame by means including a metal pivot pin for movement between an open position and a closed position, a first plastics moulding associated with said first frame, said moulding including a tubular member extending within a door aperture in use, and carrying a seal encircling said tubular member and arranged to contact the flap when the flap is in its closed position. Preferably said first frame is arranged to cooperate with the outer face of the door in use.

Preferably the assembly includes a second metal frame, a second flap pivotally mounted on said second frame by means including a metal pivot pin, and a second plastics moulding including a tubular member receiving the tubular member of the first moulding in use, and carrying draught reducing means, preferably in the form of a pair of opposed brushes arranged substantially to close the end of the second tubular plastics member adjacent said second flap.

The first and second metal frames are preferably identical to one another.

The first and second metal frames each preferably comprise a base member provided with an opening, and a pair of end members connected to the base member. The base member preferably includes spacer means1 preferably in the form of elongate ribs, for spacing the base plate from a surface upon which the frame is mounted, in use, and defining a recess housing a seal for sealing the frame to the surface, in use. The seal preferably comprises a closed cell polyethylene gasket.

According to a second aspect of the invention there is provided a letter plate assembly comprising first and second identical metal frames, a closure flap being pivotally mounted on the first frame by means including a metal pivot pin for movement with respect thereto between an open position and a closed position, and first and second telescopic tubular plastics members extending between the first and second frames.

The first and second metal frames each preferably comprise a base member provided with an opening, and a pair of end members connected to the base member.

The base member preferably includes spacer means, preferably in the form of elongate ribs, for spacing the base plate from a surface upon which the frame is mounted, in use, and defining with said end members a recess encircling said opening and housing a seal for sealing the frame to the surface, in use. The seal preferably comprises a closed cell polyethylene gasket.

The invention will further be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is front view of a letter plate assembly in accordance with an embodiment of the invention; Figure 2 is a cross sectional view along the line X-X of Figure 1; Figure 3 is a cross sectional view along the line Y-Y of Figure 1 with the assembly arranged for use with a relatively thick door; and Figures 4 and 5 are front and rear perspective views of a frame of the letter plate assembly of Figures 1 to 3.

The letter plate assembly illustrated in the accompanying drawings is intended to be mounted upon a door, in use, and comprises first and second identical aluminium frames 10, 12 to each of which is pivotally mounted an extruded aluminium flap 14. Each frame 10, 12 comprises an extruded aluminium base member 16 of generally inverted L-shaped cross section, a base plate 18 defining the long limb of the "L" and an integral flange projecting forwardly from one edge of the plate 18 defining the short limb of the "L". The upper and lower edges of the rear surface of the base plate 18 are provided with longitudinal ribs 20 and a generally rectangular opening 22 is provided in the central region of the base plate 18 by means of stamping, the opening having suitable dimensions in order to permit mail to be posted therethrough.

Left and right end members 24 are arranged to be secured to the ends of the base member 16, each end member 24 comprises an extruded aluminium member of generally L-shaped cross-section. One limb 26 of each end member 24 is arranged to be received behind the base plate 18, between the ribs 20, the rear surface of the limb 26 being generally coplanar with the rear surface of the ribs 20. Each end of the base plate 18 and each of the end members 24 is provided with a central aperture 28 and two apertures 30 one on each side of the aperture 28. The apertures 28, 30 of the base member align with the apertures 28, 30 of the end members 24, the apertures of each end member 24 being located in an elongate recess 32 provided in the rear face of the member.The end members 24 are secured to the base member 16 by means of rivets extending through the outer apertures 30 of each set of three apertures, the rivet heads being received in the recess 32 and the other limb of each end member 24 extending perpendicular to the base plate 18 such that said other limbs define respective end walls of the frame.

In use, the ribs 20 provided on the base member 10 and the limbs 26 of the end members 24 space the base plate 18 from the surface of the door, and define a recess in the base member 16 receiving a seal 36 to provide a substantially wind- and water-proof seal around the opening 22 between the frame 10 and the surface of the door. In the illustrated embodiment, the seal 36 is provided only on the outer frame 10, although such a seal 36 could be provided on both frames 10, 12 if desired. The seal 36 comprises a closed cell polyethylene gasket.

A respective extruded aluminium closure flap 14 is pivotally mounted upon each of the frames 10, 12, each flap 14 being mounted by means of a pair of steel pivot pins 38 extending through a pair of apertures 39 provided adjacent the upper edges of the end members 24 of the frames 10, 12. The pins 38 are a rotatable fit in the respective member 24 but a drive fit between a pair of elongate ribs 40 integrally formed adjacent the upper edge of the flap 14, so as to be rigidly secured thereto.

Each flap 14 is spring biased towards a closed position by means of helical steel torsion springs (not shown) received between the ribs 40.

The frame 10 and flap 14 for the outer surface of the door are provided with two such springs, each spring being arranged so that one end thereof engages with the flap 14, the other end extending through a slot in a rib 40 and engaging in an aperture 42 provided in the frame 10 to bias the flap 14 towards a closed position. The frame 12 and flap 14 for the inner surface of the door are provided with a single spring.

Associated with the frame 10 for the outer surface of the door is a plastics moulding 44 comprising a tubular region 46 of generally rectangular cross section arranged to extend through the opening 22 of the base member 16, the outer end of the tubular region 46 being provided with a peripheral flange 48 extending generally parallel to the plane of the base member 16. The flange 48 is provided with a pair of apertures arranged to align with the central aperture 28 of each set of three apertures 28, 30 provided in the end members 24 of the frame 10, integral bushings 50 being provided in the flange 48 to strengthen those parts thereof.The face of the flange 48 is recessed adjacent its junction with the tubular region 46 to receive a seal 52 in the form of a closed cell polyethylene gasket arranged, in use, to be contacted by the inner surface of the flap 14 when the flap 14 is in its closed position.

The tubular region 46 of the plastics moulding 44 is of smaller dimensions than the opening 22 provided in the frame 10, so as to be slidable within a corresponding sleeve of the moulding associated with the frame 12. The plastics moulding 44 including a thickened region 54 at the junction of the tubular region 46 and the flange 48. The region 54 takes up the clearance between the sleeve 44 and the opening 22 in order substantially to prevent lateral movement of the plastics moulding 44 with respect to the frame 10.

The frame 10 and the plastics moulding 44 are secured to one another by means of a pair of internally screw threaded metal members 56 which are driven into through bushings 50 and corresponding apertures 28 of the frame 10. The outer ends of the internally screw threaded members 56, are of enlarged diameter in order to limit penetration of the members 56. The outer surface of each member 56 is knurled in order to prevent or restrict angular movement of the member 56 with respect to the frame 10 and plastics moulding 44.

The frame 12 arranged to be secured to the inner surface of the door is also provided with a plastics moulding 58 comprising a tubular region 60 of generally rectangular cross section, the dimensions of the tubular region 60 being slightly greater than those of the tubular region 46 of the plastics moulding 44 associated with the frame 10 to be secured to the outer surface of the door, so that the tubular region 46 is slidable within the tubular region 60 in a telescoping manner, the tubular region 60 being push fit in the opening 22 of the frame 12.

The plastics moulding 58 includes a flange 62 extending generally parallel to the base plate 18 of the frame 12, the flange 62 including apertures arranged to align with the centre apertures 28 provided in the frame 12.

The outer face of the flange 62 is moulded with integral lugs 66 for mounting a pair of elongate draught excluders in the form of brushes 64, one brush being carried adjacent the upper edge of the flange, the other brush being carried adjacent the lower edge, and the brushes 64 extending towards one another substantially to close the tubular region 60. The lugs 66 define re-entrant recesses within which the brushes 64 are received as a snap-fit.

Suitable ribs or protrusions are provided on the member 60 to enable it to be snap-fitted to the frame 12.

In order to secure the letter plate assembly in position on a door the frames 10, 12 together with their associated plastics mouldings 44, 58 are positioned on the door with the tubular regions 46, 60 of the plastics mouldings 44, 58 extending into an aperture of the appropriate size provided in the door, the tubular member 46 being received within the tubular member 60. Elongate screws 68 are then introduced through the apertures 28 of the frame 12 to engage in the internally screw threaded members 56, and are then tightened to pull the frames 10, 12 against the outer and inner faces of the door and so secure the assembly in position on the door.

Since the frames 10, 12 together with the flaps 14 are identical to one another, production of the letter plate assembly is relatively simple, the number of different parts being relatively small. Moreover since each flap 14 is pivoted to a respective metal frame 10, 12 by metal pivot pins the flap mounting is particularly robust while at the same time the assembly retains the benefits of a moulded plastics construction in readily incorporating a seal 52 and brushes 64.

In order to provide an improved seal between the frame 10 and the respective surface of the door, the gasket 36 may be laminated to a larger sheet of gasket material which thus defines a flange extending outwardly from the gasket 36 towards the outer periphery of the frame 10 so as to cover substantially all of the rear surface of the frame 10 other than the portion of the frame 10 defining the opening 22. The provision of the flange extends the sealing area between the frame 10 and the face of the door.

Such an arrangement is of particular use where, rather than drilling separate apertures in the door to receive the elongate screws 68, the aperture in the door intended to receive the tubular regions 46, 60 of the plastics mouldings 44, 58 is extended so as to additionally receive the elongate screws 68. Where such an extended aperture is provided, the gasket 36 alone would be unable to provide a satisfactory seal between the frame 10 and the face of the door, but the provision of the flange covering substantially all of the rear face of the frame 10 permits the provision of a satisfactory seal.

Although the provision of the flanged gasket is described in relation to the first frame 10, it will be understood that a similar arrangement could be provided for the second frame 12.

Claims

1. A letter plate assembly comprising a first metal frame, a closure flap pivotally mounted upon the first frame by means including a metal pivot pin, for movement between an open position and a closed position, a first plastics moulding associated with said first frame, said moulding including a tubular member extending within a door aperture in use, and carrying a seal encircling said tubular member and arranged to contact the flap when the flap is in its closed position.

2. An assembly as claimed in Claim 1, further comprising a second metal frame, a second flap pivotally mounted on said second frame by means including a metal pivot pin, and a second plastics moulding including a tubular member receiving the tubular member of the first moulding in use.

3. An assembly as claimed in Claim 2, wherein the second plastics moulding is arranged to carry draught reducing means.

4. An assembly as claimed in Claim 3, wherein the draught reducing means comprises a pair of opposed brushes arranged substantially to close the end of the second tubular plastics member adjacent said second flap.

5. An assembly as claimed in any one of Claims 2 to 4, wherein the first and second frames are identical to one another.

6. A letter plate assembly comprising first and second identical metal frames, a closure flap being pivotally mounted on the first frame by means including a metal pivot pin, for movement with respect thereto between an open position and a closed position, and first and second telescopic tubular plastics members extending between the first and second frames.

7. An assembly as claimed in any one of Claims 2 to 6, wherein the second frame comprises a base member provided with an opening, and a pair of end members connected to the base member.

8. An assembly as claimed in any one of the preceding claims, wherein the first frame comprises a base member provided with an opening, and a pair of end members connected to the base member.

9. An assembly as claimed in Claim 7 or Claim 8, wherein the base member includes spacer means for spacing the base plate from a surface upon which the frame is mounted, in use, and defining a recess housing a second seal for sealing the frame to the surface, in use.

10. An assembly as claimed in Claim 9, wherein the spacer means comprises a plurality of elongate ribs.

11. An assembly as claimed in Claim 9 or Claim 10, wherein the second seal comprises a closed cell polyethylene gasket.

12. An assembly as claimed in any one of Claims 9 to 11, wherein the second seal includes an outwardly extending flange arranged to cover substantially all of the face of the base member facing the surface upon which the frame is mounted, in use.