GB2199213A

GB2199213A - Telephone handpiece housing

Info

Publication number: GB2199213A
Application number: GB08729195A
Authority: GB
Inventors: Jan Waszczuk; Tony Ziolkowski
Original assignee: Amalgamated Wireless Australasia Ltd
Current assignee: Amalgamated Wireless Australasia Ltd
Priority date: 1986-12-19
Filing date: 1987-12-15
Publication date: 1988-06-29
Also published as: GB8729195D0

Abstract

A two-part telephone handpiece housing has co-operating snap fitting formations (4, 20, 24) on co-operative parts (1, 21) to fasten the parts together. Co-operating alignment formations (5, 6, 25, 26) serve to align the parts as they are brought together to engage the snap fitting. The alignment formations also absorb impact forces delivered to the housing, to prevent transmission of the impact forces to the snap fitting formations. <IMAGE>

Description

HANDPIECE HOUSING This invention relates to the construction of telephone handpiece housings.

A major design criterion for telephone handpiece housings is that the assembly of the handpiece components should require as few operations as possible.

In addition, it is desirable that telephone handpieces are provided with a hanging recess designed to allow the handpiece to be hung on a lug, for example in the case of a wall mounted telephone. However, commonly used processes for providing a suitable blind recess in moulded articles, for example, the process known as side-coring, are difficult and expensive.

It is an object of this invention to provide a telephone handpiece housing according to the above criterion. It is a further object of the invention to provide a method of forming a telephone handpiece housing with a hanging recess which will overcome or at least ameliorate the above disadvantages.

Accordingly, this invention consists in a telephone handpiece housing comprising a front cover and a back cover, co-operating snap fitting formations thereon to fasten the covers together to form said housing and co-operating alignment formations on the covers for alignment thereof as the covers are brought together for engagement of the snap fitting formations, said alignment formations being adapted to absorb impact forces delivered to the housing to prevent transmission of impact forces to the snap fitting formations.

The snap fitting assembly of the housing provides a simplified assembly procedure with fewer steps. In addition, the absorption of impact forces by the alignment formations prevents transmission of the impact force to the snap fitting formations and reduces the likelihood of the formations being disengaged.

For preference, the front cover and rear cover are unitary mouldings. This reduces the number of components and further increases the ease and simplicity of assembly.

The alignment formations preferably comprise a transversly extending rib and a longitudinally extending rib on one of the covers which neatly fit into respective notches on the other cover. The openings of the notches are preferably tapered to guide the ribs into alignment with the neatly fitting portions of the notches.

The provision of transverse and longitudinal alignment formations provides for alignment in respective directions. It will be apparent that the ribs could be replaced for example, by a single circular formation which would provide alignment in both directions.

It is also preferred that a recess is formed in the front cover to allow the handset to be hung on a lug, for example, in the case of a wall mounted telephone.

In accordance with this invention the recess is formed by moulding the cover with a through hole and preventing access to the inside of the housing by providing barrier formations on the covers which substantially occlude the hole when the housing is assembled. The barrier formations preferably comprise two co-operating parts, one formed on each of the covers. This method of forming the recess may avoid the need for difficult and expensive moulding techniques such as side-coring. Advantageously the co-operating barrier formations may provide alignment formations which also absorb impact forces delivered to the housing.

One embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic perspective view of the front cover forming part of a handpiece housing according to this invention; Figure 2 is a schematic perspective view of the rear cover forming part of a handpiece housing according to this invention; Figure 3a is a schematic partial perspective view of the other side of the front cover of Figure 1; Figure 3b is a view similar to Figure 3a of an assembled housing including a cut away view of part of the housing; and Figure 3c is a schematic partial perspective view of the other side of the rear cover of Figure 2.

Referring to the drawings a telephone handpiece housing according to the invention comprises a unitary moulded front cover 1 and rear cover 21 which are moulded from suitable plastics material. Four snap fitting formations in the form of lugs 4 are formed on the front cover 1 for co-operation with snap fitting formations on rear cover 21 in a form of snap-fit recesses 24. The recesses 24 are formed in ribs or walls 20 spaced from the sides of rear cover 21. For the sake of clarity only the ribs 20 on one side of cover 21 are shown in the drawing. Projections 4a on lugs 4 snap-fit into recesses 24 to fasten the front cover I and rear cover 21 together to form the handpiece housing.

A transverse rib 5 and longitudinal rib 6 formed on the front cover 1 together with notches 25 and 26 formed on rear cover 21 comprise co-operating alignment formations for alignment of the covers as they are brought together for engagement of the snap-fitting lugs and recesses. The locating notches 25 and 26 have a tapered opening to guide the ribs into alignment with the neatly fitting portion of each notch which is a close tolerance fit with the rib. This allows impact forces such as would be experienced when the housing is dropped, to be absorbed or withstood by the rib and notch arrangement rather than being transmitted to the snap-fitting lugs and recesses. In this way the likelihood of the snap-fitting lugs and recesses being disengaged by impact is substantially reduced.

Provision of a transverse rib 5 and longitudinal rib 6 ensures that the covers are aligned in both the transfers and longitudinal directions.

The front cover 1 at end 2 has earpiece grid holes 10 and further snap-fit lugs 9. A grid and lugs similar to 10 and 9 are provided at the microphone end 3 of the front cover but are not shown in figure 1.

Additional snap-fit components 29 are provided at either end of rear cover 21 to co-operate with lugs 9 of the front cover. The snap-fit components 4, 9 and 29 are provided with bevelled surfaces and these act as cam surfaces to slightly deflect mating components when the handpiece is be-ing assembled. The material chosen for the handpiece is sufficiently flexible to allow the required deflection.

The housing has a recess 7 therein designed to allow the handpiece to be hung on a lug provided on a subset case, for example in the case of a wall mounted telephone. The recess is formed by an aperture in the front cover 1 surrounded by a boxed section 8 which with a tongue 28 formed on the rear cover form a barrier formation to prevent any access to the interior of the housing-by insertion of an implement through recess 7.

That is, when the housing is assembled tongue 28 fits into boxed section 8 to substantially occlude the recess.

The method of moulding front cover 1 with recess 7 may be as follows. The recess 7 is formed by having cavities conforming to the walls of boxed section 8 in one half of a two piece mould to form cover 1, and a projection on the other half of the mould which contacts the appropriate part of the first mould to form recess 7. This moulding technique avoids the need for side-coring by having a through hole but because of the boxed section 8 and tongue 28 a barrier formation is formed which substantially occludes the recess.

Transducer retaining projections such as 19 (Figure 2) are provided in the rear cover but only the arrangement at one end is shown for the sake of clarity. The assembly of the housing according to the invention is merely a matter of pressing the front cover onto the rear cover once the transducers have been positioned in the projections 19. This provides a particularly simple assembly process with few operations.

It will also be apparent that the snap-fit arrangement particularly with the ribs 20 remote from the exterior wall of rear cover 21 make it substantially impossible to disassemble the handpiece once it has been assembled.

The foregoing describes only one embodiment of the present invention and modifications may be made thereto without departing from the scope of the invention.

Claims

1. A telephone handpiece housing comprising a front cover and a back cover, co-operating snap fitting formations thereon to fasten the covers together to form said housing and co-operating alignment formations on the covers for alignment thereof as the covers are brought together for engagement of snap-fitting formations, said alignment formations being adapted to absorb impact force delivered to the housing to prevent transmission of impact forces to the snap-fitting formations.

2. A telephone handpiece housing as claimed in claim 1 in which the front cover and rear cover are unitary mouldings.

3. A telephone handpiece housing as claimed in claim 1 in which the alignment formations preferably comprise a transversely extending rib and a longitudinally extending rib on one of the covers which neatly fit into respective notches on the other cover.

4. A telephone handpiece housing as claimed in claim 3 in which the openings of the notches are preferably tapered to guide the ribs into alignment with the neatly fitting projections of the notches.

5. A telephone handpiece housing as claimed in claim 1 in which a recess is formed in the front cover to allow the handset to be hung on a lug.

6. A telephone handpiece housing as claimed in claim 5 in which the recess is formed by moulding the cover with a through hole and preventing access inside of the housing by providing barrier formations on the covers which substantially occlude the hole and the housing as assembled.

7. A telephone handpiece housing as claimed in claim 6 in which the barrier formations preferably comprise two co-operating parts, one formed on each of the covers.

8. A telephone handpiece housing as claimed in claim 7 in which the co-operating parts of the barrier formations provide alignment formations which also absorb impact forces delivered to the housing.

9. A telephone handpiece housing substantially as herein described with reference to the accompanying drawings.