security system. It is stated in the specification that the electronics of timing the pulses of electric fence
energisers are not accurate enough to ensure that energisers firing independently in a coordinated pattern
will continue doing so over a period of time. The invention provides a means of communication which ensures
that the firing of the energisers is coordinated. With the invention coordinated firing between energisers
ensures that there will be the same timed difference between all pulses on a fence at the junctions, thus
eliminating the chance of a greater magnitude shock.
[6] The patent comprises four claims. In the court a quo, the respondents relied only on claims 1 and 2 thereof. It
is common cause that the integers of claims 1 and 2 are as follows:
Claim 1
A method of transmitting energy pulses on a conductive system where such
a system includes:
(i)
two or more conductive lines
(ii)
one or more pulse generators capable of transmitting an energy pulse
along each conductive line, and
(iii)
junction points where the conductive lines are in close physical proximity
to each other
(iv)
the method is characterised by the step of:
(a)
coordinating the operation of the energy pulse generators to ensure that
the effective pulses in the vicinity of a junction point of a conductive line are
within a predetermined
(1)
pulse rate and
(2)
magnitude range
(v)
whereby pulse production is coordinated with a timing means included in
each generator, wherein the timing means determines at what times pulses
are produced by a pulse generator, and
(vi)
wherein there is provided a central control unit capable of transmitting a
synchronisation signal to each pulse generator, said synchronisation signal
acting to reset the timing means associated with each pulse generator
(vii)
Claim 2 (as above, plus)
said pulse generators operating independently until said timing means
receive a further synchronisation signal to reset them.
Page 138 of [2014] 2 All SA 134 (SCA)
[7] A pulse generator is also referred to as an energiser. The parties are agreed that these integers are all
essential integers. I, therefore, agree with the appellants that the invention comprises a combination of
physical components and method steps, acting in a particular relation to one another, which constitute the
essential features of the claims.
[8] It is common cause that the first appellant manufactures and the second appellant sells the Merlin Stealth
model M25S master and slave energisers (the "Merlin energisers"). The Merlin energisers were the central
focus of the respondents' case in the court a quo. The respondents' case rested on documentation allegedly
pertaining to the Merlin energisers and tests performed on them by Mr JT Raubenheimer, the only witness for
the respondents at the trial. The appellants closed their case without adducing any evidence.
[9] Despite the fact that in evidence Mr Raubenheimer was asked to simply read portions of documents alleged to
pertain to the Merlin energisers into the record, the respondents and the court a quo relied on the truth of the
contents of those documents. Before us the respondents relied solely on alleged Merlin energiser user
manuals and it is, therefore, only necessary to deal with them. Mr Raubenheimer testified that these manuals
were obtained by him when he purchased a set of Merlin master and slave energisers but that he may have
downloaded some of the manuals from the internet. On either basis the manuals were inadmissible as
evidence because their authenticity had not been proved. The Merlin energiser master and slave set was
purchased by Mr Raubenheimer from Unitrade 558 (Pty) Ltd t/a Nemtek Security Warehouse ("Unitrade").
There is no evidence of any connection between Unitrade and any of the appellants. And to simply say that a
document was downloaded from the internet clearly does not prove that the document is what it purports to
be. As the respondents provided no proof that the manuals originated from any of the appellants, the
question as to the probative value of the contents thereof, if any, did not arise.
[10] That leaves for consideration the evidence of Mr Raubenheimer. He testified that on 10 March 2011 he
performed certain tests on the Merlin master and slave energisers that he purchased from Unitrade. The tests
were performed with the use of an oscilloscope. An oscilloscope is capable of visualising the electric pulses
produced by energisers. According to Mr Raubenheimer, the tests demonstrated that the Merlin master and
slave energisers each has its own timer which determines at what times pulses are generated by that
energiser and that these pulses drift apart until the respective timers are resynchronised. His opinion was
that the tests made it clear that a synchronisation signal was transmitted between the master energiser,
acting as the central control unit, and the slave energiser and that the signal acted to reset the timer
associated with each pulse generator.
[11] For the reasons that follow, reliance on the evidence of Mr Raubenheimer to prove infringement of the patent
by the appellants is in my judgement flawed in a number of respects, each fatal to the case of the
respondents. First, the evidence of Mr Raubenheimer is of virtually no probative value in the circumstances.
Second, even if regard is had to his