GB2082452A - Letter plate - Google Patents

Abstract

In a letter plate comprising a hinged flap 1 which is connected to a letter plate body 2 by means of a pivotal rod and pre-loaded spring assembly (not shown), the under surface 3 of hinged flap 1 is covered with a flock material 4. This flocked material 4 engages with a raised lip 5 when hinged flap 1 is in its closed position, thus laterally displacing and compressing the flocked material such that a draught-free seal is formed. <IMAGE>

Description

SPECIFICATION Letter plate This invention relates to a letter plate of the type comprising a hinged flap and a letter plate body.

In a known construction of letter plate, a single strip of a suitable material, such as aluminium, is hinged to a letter plate body and is held in abutment to it by means of a pre-loaded spring arrangement. This design whilst being robust and simple to manufacture, has a nunber of disadvantages. For exmple, unless fairly sophisticated and precise machining of the inside surface of the letter plate flap and the outer surface of the letter plate body is performed, it is likely that when in abutment with each other, both surfaces do not form an effective seal and a draught is often the result. In addition, such letter plates tend to be rather noisy when used, and in the case of failure of the pre-loaded spring an unwanted rattle can occur.

The aim of the present invention is to provide an improved letter plate which is relatively draught free and can be easily manufactured.

According to the invention there is provided a letter plate comprising a hinged flap, one side of which is covered by a flocked material, said side normally being held in abutment against a letter plate body such that it forms a relatively draught-free seal. The letter plate body can have a raised lip on its outer surface defining an aperture through which letters are placed, the lip normally being in abutment with the flocked surface of the hinged flap such that the flocked material is displaced latrerally or compressed by the lip, thus forming a seal.

Furthermore, the hinged flap may be formed as an aluminium extrusion, onto one side of which is rolled a layer of adhesive, the flock material then being applied by an electro-static process. The flocked material itself may comprise of uniform lengths of nylon fibre.

In addition to forming a relatively draughtfree seal, the use of a flocked surface on the hinged flap has the advantage of reducing the level of noise when the letter plate is used.

Also, it has been found that the use of a flocked material endows a neat and pleasing appearance when viewed from the reverse side of the letter plate.

One embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a perspective view of an open letter plate incorporating the invention and; Figure 2 shows a sectional view of the letter plate shown in Fig. 1 in its closed position.

Referring now to Fig. 1, a hinged flap 1 is connected to a letter plate body 2 by means of a pivotal rod and pre-loaded spring assembly (not shown). The inner surface 3 of hinged flap 1 is covered by a layer of flocked material 4 which, when hinged flap 1 is closed, is in abutment with a raised lip 5 on letter plate body 2. The raised lip 5 defines a rectangular orifice 6 through which letters can be posted.

In Fig. 2 is shown a detail view of the letter plate of Fig. 1 with the hinged flap 1 held in its closed position by the pre-loaded spring assembly (not shown). Around the periphery of raised lip 5 the flocked material 4 is displaced laterally or compressed such that an indentation 7 is produced by the raised lip 5, forming a draught-free seal.

In a prefered method of construction an aluminium extrusion is coated on one side with a layer of adhesive by means of a roller, a flocked coating is applied and suitable lengths of the extrusion are then cut off to form the hinged flaps. The flocked coating itself is conveniently applied by using an electro-static process in which the particles of fibre receive a negative or positive charge and subsequently adhere to the adhesive layer in a uniformly perpendicular manner. The letter plate body is preferably made as a plastics moulding.

1. A letter plate comprised of a hinged flap, one side of which is covered by a flocked material, said side normally being held in abutment against a letter plate body such that it forms a relatively draught-free seal.

2. A letter plate according to Claim 1 in which said letter plate body has a raised lip on its outer surface defining an aperture through which letters are placed, said lip normally being in abutment with the flocked surface of said hinged flap such that said flocked material is displaced laterally or compressed by said lip, thus forming a seal.

3. A letter plate according to Claim 1 or Claim 2 in which said hinged flap is formed by an extrusion process.

4. A letter plate according to any of the preceding claims in which said hinged flap is made of aluminium.

5. A letter plate according to any of the preceding claims in which said flocked material comprises uniform lengths of nylon fibre.

6. A method of manufacturing a letter plate according to Claim 1 in which said hinged flap is formed as an extrusion, said extrusion being subsequently coated on one surface with a layer of adhesive and said flocked material being continuously applied by an electro-static process to form said flocked surface.

7. A method of manufacturing a letter plate according to Claim 6 in which said layer of adhesive is applied by a roller.

8. A letter plate substantially as herein

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Letter plate This invention relates to a letter plate of the type comprising a hinged flap and a letter plate body. In a known construction of letter plate, a single strip of a suitable material, such as aluminium, is hinged to a letter plate body and is held in abutment to it by means of a pre-loaded spring arrangement. This design whilst being robust and simple to manufacture, has a nunber of disadvantages. For exmple, unless fairly sophisticated and precise machining of the inside surface of the letter plate flap and the outer surface of the letter plate body is performed, it is likely that when in abutment with each other, both surfaces do not form an effective seal and a draught is often the result. In addition, such letter plates tend to be rather noisy when used, and in the case of failure of the pre-loaded spring an unwanted rattle can occur. The aim of the present invention is to provide an improved letter plate which is relatively draught free and can be easily manufactured. According to the invention there is provided a letter plate comprising a hinged flap, one side of which is covered by a flocked material, said side normally being held in abutment against a letter plate body such that it forms a relatively draught-free seal. The letter plate body can have a raised lip on its outer surface defining an aperture through which letters are placed, the lip normally being in abutment with the flocked surface of the hinged flap such that the flocked material is displaced latrerally or compressed by the lip, thus forming a seal. Furthermore, the hinged flap may be formed as an aluminium extrusion, onto one side of which is rolled a layer of adhesive, the flock material then being applied by an electro-static process. The flocked material itself may comprise of uniform lengths of nylon fibre. In addition to forming a relatively draughtfree seal, the use of a flocked surface on the hinged flap has the advantage of reducing the level of noise when the letter plate is used. Also, it has been found that the use of a flocked material endows a neat and pleasing appearance when viewed from the reverse side of the letter plate. One embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a perspective view of an open letter plate incorporating the invention and; Figure 2 shows a sectional view of the letter plate shown in Fig. 1 in its closed position. Referring now to Fig. 1, a hinged flap 1 is connected to a letter plate body 2 by means of a pivotal rod and pre-loaded spring assembly (not shown). The inner surface 3 of hinged flap 1 is covered by a layer of flocked material 4 which, when hinged flap 1 is closed, is in abutment with a raised lip 5 on letter plate body 2. The raised lip 5 defines a rectangular orifice 6 through which letters can be posted. In Fig. 2 is shown a detail view of the letter plate of Fig. 1 with the hinged flap 1 held in its closed position by the pre-loaded spring assembly (not shown). Around the periphery of raised lip 5 the flocked material 4 is displaced laterally or compressed such that an indentation 7 is produced by the raised lip 5, forming a draught-free seal. In a prefered method of construction an aluminium extrusion is coated on one side with a layer of adhesive by means of a roller, a flocked coating is applied and suitable lengths of the extrusion are then cut off to form the hinged flaps. The flocked coating itself is conveniently applied by using an electro-static process in which the particles of fibre receive a negative or positive charge and subsequently adhere to the adhesive layer in a uniformly perpendicular manner. The letter plate body is preferably made as a plastics moulding. CLAIMS

1. A letter plate comprised of a hinged flap, one side of which is covered by a flocked material, said side normally being held in abutment against a letter plate body such that it forms a relatively draught-free seal.

2. A letter plate according to Claim 1 in which said letter plate body has a raised lip on its outer surface defining an aperture through which letters are placed, said lip normally being in abutment with the flocked surface of said hinged flap such that said flocked material is displaced laterally or compressed by said lip, thus forming a seal.

3. A letter plate according to Claim 1 or Claim 2 in which said hinged flap is formed by an extrusion process.

4. A letter plate according to any of the preceding claims in which said hinged flap is made of aluminium.

5. A letter plate according to any of the preceding claims in which said flocked material comprises uniform lengths of nylon fibre.

6. A method of manufacturing a letter plate according to Claim 1 in which said hinged flap is formed as an extrusion, said extrusion being subsequently coated on one surface with a layer of adhesive and said flocked material being continuously applied by an electro-static process to form said flocked surface.

7. A method of manufacturing a letter plate according to Claim 6 in which said layer of adhesive is applied by a roller.

8. A letter plate substantially as herein described with reference to and as shown in the accompanying drawings.