GB2240902A

GB2240902A - Telephone with sealed compartment

Info

Publication number: GB2240902A
Application number: GB9102688A
Authority: GB
Inventors: Ian Adrian Tapping; Stephen Henry Colclough
Original assignee: Chesilvale Electronics Ltd
Current assignee: Tempo Europe Ltd
Priority date: 1990-02-08
Filing date: 1991-02-08
Publication date: 1991-08-14
Anticipated expiration: 2011-02-08
Also published as: GB9102688D0; GB2240902B; GB9002851D0

Abstract

A telephone 10 has an hermetically sealed compartment for housing the electronic components and, environmentally isolated therefrom, an openable compartment 102 for connection of cordage. Thus cordage can be replaced as required without imperilling the electronics. Access to the openable compartment 102 is by a lid 10 which may carry a hook 12 for attachment to a carrying belt. <IMAGE>

Description

TELEPHONE The present invention relates to telephones. In particular, it relates to telephones for use in a harsh environment.

Telecommunications test telephones have to be built to withstand harsh environments and arduous use.

Telephones used outdoors have to have a high degree of water and dirt resistance.

Great efforts are made by suppliers in this field to ensure reliability but the cordage on the telephone, no matter how well made, is likely to fail before the telephone. This results in telephones being opened to replace the cordage, often in a dirty environment, and subjects the interior circuit compartment to degradation or damage due to the ingress of contaminants or electrostatic damage to components.

By using a separate compartment to connect the cord the cordage compartment may be completely isolated from the interior circuit cavity. In fact, the main body of the telephone may be secured by tamper-proof fasteners to prevent deliberate or accidental access.

The present invention therefore proposes a telephone having a handset body from which cordage extends; the body having a first compartment housing electronic components and, isolated therefrom, a second compartment wherein the cordage is (preferably removably) attached to the body, there being an electrical connection between the cordage and the electronic components (generally through an environmentally sealed connector). Desirably there is a removable cover for the second compartment, e.g. to permit replacement of cordage. Preferably, the first compartment of the telephone, generally housing a circuit board, is semi-permanently sealed, and it may contain a dessicant so that the atmosphere therein is controlled. The first compartment may be secured using tamper-proof fasteners to resist unauthorised access.

If the interior of the telephone can be sealed semipermanently in this way it is possible to offer waterproof sealing and a controlled atmosphere inside by the use of a dessicant. If the atmosphere is dry there is no risk of condensation and there is no need to coat the PCB as protection against water or condensation. By not coating the PCB this reduces the risk of trapping moisture in the PCB and causing dendritic growth between PCB tracks.

Some embodiments of the present invention will now be described with reference to the accompanying drawing wherein: Fig. 1 shows part of a test telephone which is a first embodiment of the present invention; Fig. 2 is a side elevation of a test telephone which is a second embodiment; Fig. 3 is a side elevation showing the cover for the cord compartment separated from the body; and Fig. 4 is a plan view of the telephone body with the cover removed.

Both illustrated embodiments are test telephones.

In terms of electronics and functions they may be substantially conventional. Test telephones are wellknown to those skilled in the art; see for example US 4,691,336.

The first embodiment, shown in Fig. 1, is a telephone 10 which has a rear compartment closed by a cover 12 releasably mounted in its rear surface. The cover 12 is held in place by a removable fastener 14 which may be e.g. a screw. The telephone's cord 16 passes through the cover 12 to the compartment thereunder. An electrical and mechanical connection may be made between the cord and the telephone. An environmentally secure connector is used in order that the compartment is completely isolated from the interior of the telephone and the electronic components therein.

The connector also allows the cord 16 to be disconnected from the telephone 10 without compromising the seal between the compartment and the interior of the telephone.

The telephone body comprises a plurality of components 20, 22 between which is defined a compartment for electrical components. The joints 24 in the body between the components 20, 22 are environmentally sealed semi-permanently. The components 20, 22 are secured together by tamper-proof fasteners 26, and thus the interior of the telephone 10 is effectively sealed from its environment.

The embodiment shown in Figs. 2-4 is basically similar; and corresponding components are referred to by the same reference numerals. Thus the test telephone 100 has two main body components 20,22 that are (so far as the user is concerned) permanently connected to form a sealed main chamber containing the necessary electronic components. At the rear of the rear component 20, there is a recess 102 with a peripheral seal formation 104. An environmentally secure connector 106 extends into the recess 102, and the telephone cord 16 passes sealingly through the connector. Within the recess there are terminals 108 to which the cord 16 is releasably coupled. These pass sealingly through the rear body component 20, into the sealed main chamber, to carry inputs and outputs to and from the electronic components.

Also within the recess are threaded recesses 110; and tamper-proof fasteners 26 by means of which the body components 20,22 are sealed together, so that they are separable by approved personnel. A removable cover 12 has the form of a shallow elongate tray with a peripheral rim shaped to engage the peripheral seal formation 104 (which may comprise double walls 104a, 104b with a sealing gasket between them which is engageable by the tray's rim when this engages between the double walls).

Screw fasteners 14 extend rotatably but sealingly through the cover 12 so as to be engageable with the threaded recesses 110 to seal the cover 12 to the body. The rear of the cover 12 has hook means 120 so that the telephone can be suspended e.g. from an engineer's belt.

The telephone may have provision for battery power.

A battery compartment 120 is defined within the recess 102, so as to be accessible once the cover 12 has been removed.

Claims

1. A telephone comprising a handset body and cordage, said handset body comprising a lid portion and a first body portion shaped to define an enclosed electronics compartment and a cordage connection compartment; said lid portion being adapted to be sealed releasably to the first body portion to close off said cordage connection compartment, removal of the lid portion exposing the interior of said cordage connection compartment; said first body portion further comprising electrical connection means located within said cordage connection compartment for electrical connection of said cordage; electronic circuitry located within said enclosed electronics compartment; and electrical conductor means for electrically coupling said electrical connection means to said electronic circuitry; said enclosed electronics compartment being environmentally isolated from the environment and from the interior of said cordage connection compartment, whereby the cordage connection compartment is openable by removal of said lid portion to permit disconnection and connection of cordage without influencing the environment within the enclosed electronics compartment.

2. A telephone according to claim 1 wherein said first body portion comprises two body parts between which said enclosed electronics compartment is defined; and sealing means whereby said parts are sealed together; said sealing means comprising a seal element engaged between said parts, and tamper-proof fasteners for locking the body parts together.

3. A telephone according to claim 1 further including lid seal means for permitting the sealing connection of said lid portion to said body portion.

4. A telephone according to claim 3 wherein said lid seal means comprises, on one of said lid portion and said body portion, a peripheral rim portion, and, on the other one of said lid portion and said body portion, wall means defining a channel in which said peripheral rim portion is receivable.

5. A telephone according to claim 1 further including an environmentally secure connector which extends in use from the exterior to the interior of the cordage compartment; said cordage extending sealingly through said connector.