NZ530925A - A pulse generator circuit including multiple channels for storing and discharging energy - Google Patents

Abstract

Circuitry for a pulse generator with particular application to an electric fencing system is disclosed. The circuit 8 includes at least two channels 11 capable of receiving, storing, and discharging energy, switching means 10 for each channel, and a controller that is configured to control the charging and discharging of the channels in a sequential cycle so that the channels are charged and discharged for an equal period. This ensures that the components of each channel have even wear due to stress cycles, prolonging the life of the apparatus.

Description

PATENTS FORM NO. 5 Fee No. 4: $250.00 After Provisional No: 530925 Dated: 2 February 2004 PATENTS ACT 1953 COMPLETE SPECIFICATION A CIRCUIT WE Gallagher Group Limited, a New Zealand company of Kahikatea Drive (no number), Hamilton, New Zealand hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: Pro- wiv Ofee o, iM > 'V 2 7 JA:: 223 A CIRCUIT TECHNICAL FIELD This invention relates to a circuit.

In particular, this invention relates, though not solely, to a circuit for an electrical pulse 5 generator used by an energiser within an electric fencing system.

BACKGROUND ART A standard electrical energiser typically includes an energy storage element, such as a capacitor, a switching device and a transformer. In use the electrical energy stored in the capacitor is rapidly discharged (as a discharge pulse) through the transformer 10 onto the wires of an electric fence.

High energy dissipation within large energisers causes component failure as a result of the excessive heating occurring inside the energiser housing. Component failure will prevent the energiser from outputting the desired or anticipated voltage on the electric fence wires for the required duration. By reducing dissipation within an 15 energiser (and therefore heating) component wear-out causing component failure will be substantially slowed.

Furthermore, the repeated discharge of high energy pulses is likely to cause component wear-out from the resulting stress cycles, which will invariably contribute to component failure within energiser components and associated circuitry.

One approach to minimising component wear on and heat dissipation within energisers is disclosed in US Patent No. 6,020,658A. This patent discloses circuitry for an energiser having the ability to switch between storage elements associated with the energiser. 2 James & Wells ref: 29598/16 However, the design of this energiser requires that there is a first storage element (and associated circuitry) that is constantly in the charge path of the power source to which it is connected. This means that under light fence loading conditions (in which case most of the energy stored in the storage element will be dissipated in the 5 energiser circuits and transformer) that first storage element (and associated circuitry) will always be in the charge path and consequently will have more stress cycles associated with it than with the second or subsequent storage elements (and associated circuitry). This will result in uneven wear on each storage element (and associated circuitry) which will increase the chance that the energiser will fail since 10 failure of the first storage element (and associated circuitry) will prevent the energiser from operating.

It is therefore an object of the present invention to provide a circuitry for a pulse generator, energiser or electric fence system which goes at least some way towards overcoming the above disadvantages or which will at least provide the public with a 15 useful choice.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency 20 of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be 25 attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed 3 James & Wells ref: 29598/16 components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

Further aspects and advantages of the present invention will become apparent from 5 the ensuing description which is given by way of example only.

DISCLOSURE OF INVENTION According to one aspect of the present invention there is provided circuitry for a pulse generator which includes: at least two channels capable of receiving, storing and discharging energy, wherein associated with each channel is a switching means, and the circuitry characterised in that the switching means can exclude or include the associated channel from an operation of the generator.

According to another aspect of the present invention there is provided a controller adapted to operate circuitry as described above.

According to another aspect of the present invention there is provided a pulse generator which includes circuitry as described above.

According to another aspect of the present invention there is provided an electric fence system which includes circuitry as described above.

The present invention is adapted to provide circuitry, preferably for a pulse generator. 20 The applicants envision that such circuitry may be adapted for use within a pulse generator employed within an energiser for an electric fencing system, and reference throughout this specification will also be made to the present invention being used in this application. 4 James & Wells ref: 29598/16 However, those skilled in the art should appreciate that other uses for and applications of such circuitry are envisioned and reference to the above only throughout this specification should in no way be seen as limiting.

For the purposes of this specification a pulse generator may be defined as, yet need 5 not be limited by the definition as a device that is configured to generate single or multiple voltage electrical pulses.

Preferably the circuitry includes at least two channels capable of receiving, storing and discharging electrical energy.

In a further preferred embodiment the circuitry may be configured to receive electrical 10 energy from any one or a combination of power sources such as batteries, solar or mains supply.

The electrical energy received may be stored within the channel, preferably by at least one electrical charge or energy storage device incorporated into the channel. In a preferred embodiment a capacitor may be provided as an energy storage device. 15 Those skilled in the art should appreciate that the energy storage device employed in conjunction with the present invention may be constructed in any number of ways using a variety of materials and need not be limited to a capacitor.

Once the capacitor(s) has been charged to the required voltage the energy stored may be discharged via discharge circuitry to a transformer (or other electrical energy 20 transfer device). Such discharge circuitry may be formed from any appropriate circuitry known to those skilled in art. Furthermore, such discharge circuitry may be configured to, at least in part, shape the pulse transmitted from the energy storage device(s).

James & Wells ref: 29598/16 Therefore, each channel may be considered to include an energy storage device and preferably the necessary input and output circuitry to facilitate charging the energy storage device and discharging energy stored in the energy storage device.

Preferably each channel has associated with it a switching means which is adapted to 5 exclude or include the channel from an operation of the pulse generator.

An operation of the pulse generator may be considered for the purposes of this specification to include the step of receiving electrical energy from a power source followed by the further step of discharging the energy stored to a transformer. In such instances a switching means may be adapted to add a channel to a charge path, 10 with this addition being facilitated through connecting the channel to one or more powers sources. The channel involved can also be removed from such a charge path through disconnecting a switch linking the channel to one or more power sources.

In a preferred embodiment the switching means may be provided by an electronic switching means.

In some embodiments such switching means may be configured using a silicon-controlled rectifier(s) (SCR) or other appropriate solid- state circuit switching mechanism, such as a triac. However in alternative embodiments other forms of switching means, such as for example, field effect or bipolar transistors may also be employed in conjunction with the present invention if required. It should be 20 appreciated that any number of a variety of switching devices including electronic, optical switches or mechanical devices may also be employed as switching means by the present invention.

In one configuration when a switching means is open then the channel associated with the switching means has effectively been switched out. Similarly, in that 25 configuration when a switching means is closed the channel associated with the switching means has been switched in. 6 James & Wells ref: 29598/16 Appropriate positioning of the switching means within the circuitry of the present invention may enable any one or more of the channels to be switched into or out of the circuit or charge path formed. For example, by positioning a switching means between the power source and a channel the energy storage device associated with 5 that channel will be charged by the power source, and all channels which remain switched out will not be charged.

In a preferred embodiment the circuitry provided may include further discharge circuitry in the form of a single discharge switch common to all channels present in the circuitry provided. In such an embodiment all charged channels may be 10 discharged simultaneously through a transformer via the single discharge switch.

Alternatively, each channel may have associated with it a single separate discharge switch and transformer through which stored energy may be discharged.

Similarly, by positioning switching means between each channel and the transformer the energy storage devices associated with each channel that are switched in will 15 dissipate the stored energy simultaneously to the transformer. The channels which remain switched out will not dissipate the stored energy until such a time as they are switched in. Accordingly, if all channels are switched in then all channels will be discharged simultaneously through the transformer to the electric fence.

Accordingly, use of a switching means in either of the above arrangements can 20 effectively include or exclude a channel from either one or both of the steps of receiving electrical energy from the power source and/or of discharging the energy stored to the transformer.

In a preferred embodiment there is provided a controller which is adapted to operate the circuitry of the present invention. In such embodiments the controller provided 25 may be adapted to transmit control signals to at least one switching means and at least one discharge switch to effect the required charging and discharging of at least 7 James & Wells ref: 29598/16 one channel. Such a controller may be adapted to control which channels are charged and/or which channels are discharged. The number of storage devices charged and eventually discharged into the transformer may be determined by fence loading, component loading (such as temperature levels within the energiser circuitry) 5 or performance and the controller may be configured to operate the circuitry in response to such conditions.

The controller may be configured or assembled in any number of ways using any variety of appropriate constructions materials. However, it is envisaged that a controller used in conjunction with the present invention may incorporate processing 10 or computing capabilities such that it may apply a set of rules to thereby transmit appropriate signals to the circuitry in response to operating conditions. The signals transmitted to the circuitry may be indicative of the voltage which should be on the energy storage device(s) so as to give the desired output on the fencing wires when the energy storage device(s) are discharged. The controller may then switch in or 15 switch out channels as appropriate to allow the energy storage device(s) to be charged or discharged as required.

For example, current fence load may be calculated by measuring the voltage of the previous fence pulse. Under light fence load conditions only one channel may be needed to maintain effective fence voltage. In this case the controller may transmit 20 appropriate signals to the circuit components to effectively switch in only one channel and switch out all other channels. If fence loading increases the controller may transmit the required signals to switch additional channels in.

In some embodiments such circuitry may be adapted to control which channel is charged or discharged depending on the timing of when other channels have been 25 charged or discharged. For example, in a further preferred embodiment each of the channels provided may be charged and discharged in a sequential or cyclic manner one after the other if a single channel only is to be discharged at one time. 8 James & Wells ref: 29598/16 In some embodiments the controller may also be adapted to isolate faulty channels from the operation of the energiser or pulse generator to be provided. For example in such instances the controller may prevent the charging or discharging of a channel if the channel has been detected to be faulty.

Preferably there is provided an energiser which includes circuitry as described above.

Preferably there is provided an electric fence system which includes circuitry as described above. An energiser incorporating a pulse generator having the circuitry of the present invention may be used in conjunction with an electric fencing system.

The present invention provides many advantages over the prior art.

Such a configuration enables component wear to be evenly distributed evenly amongst all channels. For example, if there are 'n' channels and only one is required to maintain an effective voltage on the fence the controller may transmit signals to effectively switch between each single channel in the circuit at regular intervals. In such an embodiment each channel will only be in use 1/n of the time period, which is 15 of advantage.

Further advantages of such a configuration include that when components in the circuitry fail the pulse generator may be able to detect the fault and simply switch that channel out. In this way the pulse generator may be able to continue to function even though a channel has failed.

Another advantage of such a configuration is that multiple cheaper switches can be used instead of one expensive main switch, which represents a cost saving.

Use of such circuitry will provide a means for controlling input power consumption to suit the output energy requirements of the electric fencing system, which is of advantage. Appropriate and controlled input power consumption will also minimise 9 James & Wells ref: 29598/16 waste energy dissipation (in the form of heat) within resistive components associated with an electric fencing system which is advantageous.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the following 5 description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 is a basic schematic block diagram of the electronic components associated with a circuit used in a prior art pulse generator; Figure 2 is a basic schematic block diagram of the electronic components 10 associated with a circuit used in a pulse generator in accordance with a preferred embodiment of the present invention, and Figure 3 is a basic schematic block diagram of the electronic components associated with a circuit used in a pulse generator in accordance with an alternative embodiment of the present invention, and Figure 4 is a basic schematic block diagram of the electronic components associated with a circuit used in a pulse generator in accordance with a further alternative embodiment of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION With reference initially to Figure 1, a circuit 1 used in a prior art pulse generator is 20 shown which includes power source 2, channels 3a and 3b, discharge switch 5 and transformer 6. Associated with channel 3b is switching means 4. Channels 3a and 3b each comprise at least one energy storage device (not shown) and circuitry (not shown) which is configured to enable energy to be received into energy storage device of the channels and subsequently discharged from same via transformer 6 to James & Wells ref: 29598/16 an electric fence. In normal use, the energy stored in the energy storage devices is rapidly discharged (as a discharge pulse) through transformer 6 via discharge switch 5 onto the fencing wires of an electric fence (not shown). It should be appreciated that when switch 5 is open channel 3a or 3b will be prevented from discharging stored 5 energy to transformer 6. Similarly, when switch 4 is closed it is to be understood that channel 3b will be charged by power source 2.

However, channel 3a is always in the charge path (generally indicated by arrow 7) and cannot be switched out since no switch is present in the charge path. Under light fence loading conditions (in which case most of the energy stored will be dissipated 10 as heat in either or both the pulse generator circuitry and/or the transformer) channel 3a will always be in use and consequently will have more stress cycles associated with it than that of channel 3b. This will result in uneven wear on each of channels 3a and 3b and their associated circuitry. This will result in eventual failure of components associated with channel 3a, thereby preventing the pulse generator from 15 operating.

With reference now to Figure 2 in which there is shown a basic schematic block diagram of the electronic components associated with a circuit used in a pulse generator in accordance with a preferred embodiment of the present invention.

It can be seen that circuit 8 includes power source 9, channels 11 (comprising 20 channels 11a, 11b, 11c and 11 n), discharge switch 12 and transformer 13.

Associated with each channel 11 is a switching means 10 (comprising switches 10a, 10b, 10c and 10n). The use of the 'n' in the labelling of components denotes a plurality of such a component. As with Figure 1 each of the above channels 11 include at least one energy storage device (not shown) and discharge circuitry (not 25 shown) which are configured to enable energy to be received into energy storage device of the channels and subsequently discharged from same via transformer 13 to an electric fence. 11 James & Wells ref: 29598/16 By switching each and every switching means 10 to a closed position the energy storage devices of channels 11 will be simultaneously charged by the power source 9. By switching any specific switch to an open state the channel associated with that switching means will remain uncharged. All channels 11 which have been charged 5 will then be simultaneously discharged through the transformer 13 where single discharge switch 12 is closed.

With reference now to Figure 3 in which there is shown a basic schematic block diagram of the electronic components associated with a circuit used in a pulse generator in accordance with a preferred embodiment of the present invention.

There is provided a circuit 14 having multiple discharge switches 15 (comprising switches 15a, 15b, 15c and 15n) which are located between each channel 16 (comprising channels 16a, 16b, 16c and 16n) and transformer 17. Accordingly, the energy storage devices associated with each channel 16 that are switched in (ie having their associated switch closed) will dissipate the energy stored simultaneously 15 to transformer 17. The channels having their associated switch open will remain switched out will not dissipate energy until such a time as they are switched in. Accordingly, if all channels 16 are switched in then all be discharged simultaneously through the transformer 17a and onto the electric fence.

Appropriate use of the switching means in either of the arrangements shown in 20 Figures 2 and 3 can effectively include or exclude a channel from either one or both of the steps of receiving electrical energy from the power source and/or of discharging the energy stored to the transformer for subsequent delivery to an electric fence. A controller (not shown) is configured to transmit the necessary signals (by applying a set of rules) to open or close switches as appropriate to enable the energy storage 25 device(s) of each channel to be appropriately charged or dissipated as required. 12 James & Wells ref: 29598/16 With reference now to Figure 4 in which there is shown a basic schematic block diagram of the electronic components associated with a circuit used in a pulse generator in accordance with a further preferred embodiment of the present invention.

There is provided a circuit 18 having multiple discharge switches 15 (comprising 5 switches 15a, 15b, 15c and 15n) which are located between each channel 16 (comprising channels 16a, 16b, 16c and 16n) and multiple transformers 17 (comprising transformers 17a, 17b, 17c and 17n). Accordingly, if all channels 16 are switched in using switches 15 then all will be discharged simultaneously through the transformers 17 and onto the electric fence. Similarly, by selectively opening or 10 closing switches 15 the switching means can effectively include or exclude a channel 16 from discharging the energy stored to one or other or all of the transformers 17.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof. 13 James & Wells ref: 29598/16

Claims (1)

1. WHAT WE CLAIM IS: Circuitry for a pulse generator which includes, at least two channels capable of receiving, storing and discharging energy, wherein associated with each channel is a switching means, a controller adapted to transmit control signals to at least one switching means, said circuitry being charaterised in that a switching means is adapted to exclude or include an associated channel from the operation of the pulse generator, wherein the controller is configured to control the charging and/or discharging of the channels in a sequential cycle such that each channel is charged and/or discharged for a substantially equal period to each other. Circuitry for a pulse generator as claimed in claim 1, wherein each channel includes an energy storage device. Circuitry for a pulse generator as claimed in claim 2, wherein a capacitor is provided as an energy storage device. Circuitry for a pulse generator as claimed in any previous claim, which is adapted to receive electrical energy from one or more power sources. Circuitry for a pulse generator as claimed in any previous claim, wherein the position of a switching means is adapted to add or remove a channel from a charge path. Circuitry for a pulse generator as claimed in either claim 4 or claim 5, wherein a switching means is located between a power source and the associated channel. Circuitry for a pulse generator as claimed in any previous claim, wherein a switching r means includes an electronic switching device. '* ' J 'bV| , vj f 7 '• ■ I : , I..U3 14 James & Wells ref: 29598/16 8. Circuitry for a pulse generator as claimed in any previous claim, wherein a switching means includes a silicon controlled rectifier. 9. Circuitry for a pulse generator as claimed in any one of claims 1 to 7, wherein a switching means includes a field effect transistor. 10. Circuitry for a pulse generator as claimed in any one of claims 1 to 7, wherein a switching means includes a bipolar transistor. 11. Circuitry for a pulse generator as claimed in any one of claims 1 through 7, wherein a switching means includes a triac. 12. Circuitry for a pulse generator as claimed in any one of claims 2 to 11, which includes a single discharge switch adapted to discharge the energy storage devices of all channels. 13. Circuitry for a pulse generator as claimed in any one of claims 1 through 12, wherein each channel includes a single discharge switch. 14. Circuitry for a pulse generator as claimed in any previous claim, wherein the controller is adapted to transmit control signals to at least one switching means and at least one discharge switch. 15. Circuitry for a pulse generator as claimed in claim 14, wherein the controller is adapted to control which channels are charged and/or which channels are discharged. 16. Circuitry for a pulse generator as claimed in any one of claims 14 to 15, wherein the controller is adapted to prevent the charging and/or discharging of the channel if said channel is determined to be faulty. 17. A pulse generator which includes circuitry as claimed in any one of claims 1 through 12. f—-r—• f - « . _ o - i 3 15 James & Wells ref: 29598/16 18. An electric fence system which includes the circuitry for a pulse generator as claimed in any of claims 1 through 17. 19. Circuitry for a pulse generator substantially as herein described with reference to and as illustrated by figures 2 to 4 and/or examples of same. 20. A method of manufacturing circuitry for a pulse generator substantially as herein described with reference to and as illustrated by figures 2 to 4 and/or examples of same. GALLAGHER GROUP LIMITED by their authorised agents 16 James & Wells ref: 29598/16