AU2008202710B2

AU2008202710B2 - Protective Shroud

Info

Publication number: AU2008202710B2
Application number: AU2008202710A
Authority: AU
Inventors: Brian Sorensen
Original assignee: Altronic Distributors Pty Ltd
Current assignee: Altronic Distributors Pty Ltd
Priority date: 2001-10-05
Filing date: 2008-06-19
Publication date: 2009-01-22
Anticipated expiration: 2022-10-04
Also published as: AU2008202710A1

Description

P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Actual Inventor Address for service is: Altronic Distributors Pty Ltd Brian Sorensen

WRAYS

Ground Floor, 56 Ord Street West Perth WA 6005 Attorney code: WR Invention Title: Protective Shroud The following statement is a full description of this invention, including the best method of performing it known to me:- 00 N "Protective Shroud" Technical Field This invention relates to a protective shroud for a loud speaker.

Background of the Invention 00 5 Public address systems installed in buildings and other structures utilise loud 0speakers connected to a public address amplifier from which signals are transmitted to the loud speakers. Each loud speaker incorporates a transformer to match the speaker impedance with the output impedance of the amplifier. The transformer incorporates a terminal block, a capacitor, and a plurality of exposed terminals, the arrangement being that the capacitor is electrically connected to one of the exposed terminals according to the performance characteristics required for the loud speaker. Typically the terminals are in the form of male spade connectors, with the capacitor being provided with a lead terminating at a female spade connector which can be selectively fitted onto any one of the male spade connectors as necessary according to the performance characteristics required for the speaker.

With such an arrangement, the male spade connectors to which the female spade connector are not fitted remain exposed when the loud speaker is installed and the public address system is in operation. This presents a danger as there is a possibility that a person might inadvertently contact the exposed connectors and receive a shock.

The present invention seeks to provide a protective shroud which can be fitted to the transformer for the purposes of preventing inadvertent contact with the exposed live terminals.

-3-1- SDisclosure of the Invention In accordance with a first aspect of the present invention, there is provided a

INO

protective shroud for a loud speaker having a transformer incorporating a plurality of exposed terminals disposed in an array, the protective shroud comprising a body adapted to be mounted on the transformer, the body having a c protective wall adapted to cover the terminals to prevent external contact c therewith and an access opening in the protective wall to facilitate access of an 00 oo electrical cable to the terminals.

Preferably, the terminals are in a spaced-apart, side-by-side relationship, and the access opening in the protective wall comprises a slot.

The body may further comprise a side wall and a pair of opposed end walls, the end walls being adapted to releasably engage the transformer for retaining the protective shroud in position on the transformer. For this purpose, the end walls may be configured as tangs for engaging the transformer with a snap-on action.

The transformer may have a terminal block mounted thereon and the protective wall may incorporate a plurality of lugs adapted to locate in openings in the terminal block so as to assist location of the protective shroud in position on the transformer.

The transformer may be provided with a capacitor having a lead adapted to be selectively connected to one of the terminals. In such a case, the protective shroud may be configured to receive and retain the capacitor in position on the transformer when the protective shroud is fitted to the transformer. This may be achieved by configuring the side wall of the protective shroud to create a space for accommodating the capacitor.

In accordance with a second aspect of the present invention, there is provided a protective shroud for a loud speaker having a transformer incorporating a plurality of exposed terminals disposed in an array, the protective shroud -3-2comprising a body adapted to be mounted on the transformer, the body having a F protective wall adapted to cover the terminals to prevent inadvertent contact by a c- person therewith and an access opening in the protective wall to facilitate access IDof an electrical cable to the terminals such that the electrical cable is connectable to and detachable from the terminals while the body is mounted on the transformer.

Preferably, the access opening in the protective wall comprises a slot.

00oo Preferably, the body further comprises a side wall and a pair of opposed end walls, the end walls being adapted to releasably engage the transformer for retaining the protective shroud in position on the transformer.

Preferably, the end walls are configured as tangs for engaging the transformer with a snap-on action.

Preferably, the protective wall incorporates a plurality of lugs adapted to locate in openings in a terminal block mounted on the transformer to assist location of the protective shroud in position on the transformer.

Preferably, the body is configured to receive and retain a capacitor in position on the transformer when the protective shroud is fitted to the transformer.

Preferably, the side wall of the protective shroud is configured to create a space for accommodating the capacitor.

00 CI Brief Description of the Drawings The invention will be better understood by reference to the following description of one specific embodiment thereof as shown in the accompanying drawings, in which: c- 5 Figure 1 is a schematic perspective view of a protective shroud according c-i to the embodiment shown about to be fitted onto a loud speaker; 00 cFigure 2 is a view similar to Figure 1 with the exception that the protective shroud is shown in position on the loud speaker; Figure 3 is a perspective view of the protective shroud from the upper side thereof; Figure 4 is a perspective view of the protective shroud from the under side thereof; Figure 5 is an upper plan view of the protective shroud; Figure 6 is an under plan view of the protective shroud; Figure 7 is a side view of the protective shroud; Figure 8 is an elevational view of the protective shroud from one end thereof; and Figure 9 is an elevational view of the protective shroud from the other end thereof.

(3 00 C Best Mode(s) for Carrying Out the Invention

;Z

The embodiment shown in the drawings is directed to a protective shroud 10 for use with a conventional loud speaker 11 which incorporates a transformer 13 for matching the speaker impedance with the output impedance of an amplifier for a public address system (not shown) in which the loud speaker is used.

N The transformer 13 is of known kind and comprises a transformer body 00 oO 0incorporating a plurality of exposed terminals 17 arranged in a curved array, as C shown in Figures 1 and 2 of the drawings. The transformer has a terminal block 19 mounted on the transformer body, and a capacitor 21.

The terminal block 19 incorporates a plurality of terminal elements 23, each comprising opposed openings 25 to receive the ends of electrical cabling and securing screws 26 for securing the ends of the cabling in position in the terminal elements 23. In this embodiment, there are four terminal elements, with the four terminal elements being bridged together in pairs, one being an active or feed pair 27 and the other being a neutral, return, or common pair 29. Each pair 27, 29 is adapted to receive a cable lead for operatively connecting the loud speaker to the system amplifier. One cable lead is a feed lead which is connected to the feed or active pair 27 and the other cable lead is a return lead which is connected to the neutral, return or common pair 29.

The transformer 13 has a lead 31 which is connected to one of the block elements 23 in the active terminal block pair 27.

The capacitor 21 has a first lead 33 which is connected to one of the terminal elements 23 in the common terminal block pair 29, and a second lead 35 which is adapted to be connected to a selected one of the exposed terminals 17.

00 -6- 0 c In this embodiment each terminal 17 is in the form of a male spade connector and the second lead 35 of the capacitor 21 has a terminal end fitted with a o complementary female spade connector 36 for connection to a selected one of the male spade connectors 17.

The protective shroud 10 comprises a body 40 moulded from a suitable N electrically-insulating material and having a top wall 41 which provides a N protective wall as will be explained later, a side wall 43, and two opposed end oo Swalls 45. The end walls 45 are each configured as tangs for engaging the body N 15 of the transformer with a snap-on action in the manner shown in Figure 2 of the drawings.

The protective wall 41 has an edge 51 incorporating a plurality of lugs 53 dimensioned and arranged to be received in the openings 25 in the terminal block 19, as shown in Figure 2 of the drawings, in order to assist location of the protective shroud 10 in position on the transformer 13.

The protective wall 41 also incorporates an access opening 55 to facilitate access to the exposed terminals 17. When the protective shroud 10 is fitted into position on the transformer 13 in the manner shown in Figure 2, the protective wall 41 prevents external contact with the terminals 17. However, the access opening 55 provides a passage through which the second lead 35 of the capacitor 21 can extend for connection to one of the terminals 17. As can also be seen in Figure 2 of the drawings, each of the terminals 17 is visible through the access opening 55, however the size of the access opening inhibits inadvertent contact with the terminals.

In this embodiment, the access opening 55 is in the form of an arcuate slot, the curvature of which corresponds to the curved array of the terminals 17.

00 N The side wall 43 of the protective shroud 10 incorporates a bulbous portion 57 which defines a cavity 59 in which the capacitor 21 can be accommodated. With this arrangement, the protective shroud 10 can be utilised to retain the capacitor 21 in position with respect to the transformer 13 without the need for separate fixings for securing the capacitor to the transformer body N As alluded to above, the protective shroud 10 prevents inadvertent contact with N the terminals 17 (which are live during operation of the public address system) 00 Swhile allowing access to each of the terminals 17 to connect the second lead Sof the capacitor 21 to a selected one of the terminals 17. The particular terminal 17 selected depends upon the required performance characteristics of the loud speaker.

From the foregoing, it is evident that the present embodiment provides a simple yet highly effective arrangement for enhancing safety associated with use of the loud speaker 11 by inhibiting inadvertent contact with the terminals 17.

Additionally, the protective shroud also provides the secondary function of retaining the capacitor 21 in position with respect to the transformer body In the embodiment described, the protective shroud 10 is designed for use with a transformer 13 having a four-way terminal block 19 and a capacitor 21.

It should be appreciated that a protective shroud according to the invention can be used with other transformer arrangements. For example, there may be instances where there is some other form of terminal block, such as a two-way terminal block. A protective shroud according to the invention can be configured appropriately to fit such a transformer.

-8- 00 c Additionally, there may be instances where a transformer is not provided with a capacitor, in which case a protective shroud according to the invention would not need to be configured to provide a cavity for receiving a capacitor.

It should be appreciated that the scope of the invention is not limited to the scope of the embodiment described.

SThroughout the specification, unless the context requires otherwise, the word oo 00 6 "comprise" or variations such as "comprises" or "comprising", will be understood C to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Claims

1. A protective shroud for a loud speaker having a transformer incorporating a INO O plurality of exposed terminals disposed in an array, the protective shroud comprising a body adapted to be mounted on the transformer, the body having a protective wall adapted to cover the terminals to prevent inadvertent N contact by a person therewith and an access opening in the protective wall to c facilitate access of an electrical cable to the terminals such that the electrical 00 oo cable is connectable to and detachable from the terminals while the body is mounted on the transformer.

2. A protective shroud according to claim 1 wherein the access opening in the protective wall comprises a slot.

3. A protective shroud according to claim 1 or 2 wherein the body further comprises a side wall and a pair of opposed end walls, the end walls being adapted to releasably engage the transformer for retaining the protective shroud in position on the transformer.

4. A protective shroud according to claim 3 wherein the end walls are configured as tangs for engaging the transformer with a snap-on action.

A protective shroud according to any one of the preceding claims wherein the protective wall incorporates a plurality of lugs adapted to locate in openings in a terminal block mounted on the transformer to assist location of the protective shroud in position on the transformer.

6. A protective shroud according to any one of the preceding claims wherein the body is configured to receive and retain a capacitor in position on the transformer when the protective shroud is fitted to the transformer.

7. A protective shroud according to claim 6 wherein the side wall of the protective shroud is configured to create a space for accommodating the capacitor. 00 O o

8. A protective shroud substantially as herein described with reference to the Saccompanying drawings. 00 o