The present invention relates to a power strip device,
i.e. an electrical device and apparatus to be use for the splitting of a single
AC power outlet into a plurality of AC power outlets. More particularly, the present
invention relates to a switched electrical power strip device to be used in combination
with home electronic devices which are connected to the power strip device for receiving
AC mains power therefrom and has an electronic detector circuit for switching on
and off a plurality of AC power outlets to which the electronic device such as a
TV set, a VCR, a DVD player, a DVD player and recorder, a satellite receiver, a
surround sound amplifier or receiver, a CD player, a tape recorder, a cassette recorder,
a stereo amplifier, a record player or the like.
In the present context, a home electronic device is to
be construed as a generic term including any electrical apparatus for office, home
or domestic use or personal use including the above mentioned apparatuses or any
other similar apparatus.
Within the computer filed there have already been made
attempts to provide technical solutions for saving energy by providing switched
strip power strip devices, which power strip devices are connectable to an AC power
outlet and to e.g. an USB terminal of the computer. Within the power strip device,
a relay such as a solenoid or solid state relay may be housed for switching the
AC power outlets of the power strip device on and off controlled by the computer
through its USB connection. The relay is powered directly from the USB output of
the computer and the power strip includes a number, e.g. four or six AC power outlets,
which are all switched on and off simultaneously controlled by the USB outlet.
The commercially available products of this type have generally
been manufactured as highly expensive equipment or alternatively as extremely low
cost products, which for the sake of reducing the price, have been manufactured
without taking due consideration to the safety requirements when combining a low
voltage control side and a high voltage AC mains supply side. The concern relating
to the safety aspect is of course far more pronounced in e.g. Europe as compared
to the Far East and North America, since in Europe, the AC mains supply voltage
is today 230 V, whereas in the Far East and in North America, the AC mains supply
voltage is merely 110-120V.
Examples of electrical power strip devices of this kind
are described in: US 4,675,537, US 5,097,249, US 5,164,609, US 5,424,903, US 5,550,649,
US 5,579,201, US 5,841,424, US 6,211,581, US 6,509,655, US 6,526,516, US 6,586,849
and US 6,586,849. Reference is made to the above US patents and the above US patents
are further hereby incorporated in the present specification by reference.
Within the present technical field, i.e. the field of home
electronic devices, attempts have also been made to provide switched power strip
devices for the turning on or turning off of a plurality of electronic devices.
Examples of electrical power strip devices of the kind are described in US 6,642,852
and US Des. 411,169. Reference is made to the above US patents and the above US
patents are further hereby incorporated in the present specification by reference.
The applicant company and in particular, the inventor has
realised that the technical solutions commercially available within the technical
field of switched power strip devices call for improvement and refinement, in particular
in terms of safety considerations and further in terms of safe and reliable operation,
An object of the present invention is to provide a power
strip device of the above described kind having a plurality of switched AC power
outlets, which electric power strip device fulfils the requirements as to separation
between the low voltage side and the high voltage AC mains supply side and further,
provides a safe and swift switching operation as distinct from the prior art simple
relay switches which in some instances may turn out to be unreliable and malfunctioning.
It is a further object of the present invention to provide
a power strip device which may be used in a concealed position having the AC power
outlets concealed behind e.g. a piece of furniture and allowing the power strip
device to be safely switched on and off by means of a remote control unit to be
used in its conventional mode for turning on and off e.g. a TV set and further e.g.
a DVD player or any other of the apparatuses mentioned above.
The above object together with numerous other advantages
and features, which will be evident from the below detailed description of the presently
preferred embodiment of the power strip device according to the present invention,
is according to the teachings of the present invention obtained by a power strip
- a housing of an electrically insulating material and of an elongated configuration
defining opposite end surfaces, a top surface, a bottom surface and opposite side
- an electrical cord including a live wire and a neutral wire, the electrical
cord extending from the one end surface of the housing through a first pull relief
bushing and having at its remote end an AC plug to be connected to an AC mains outlet
for the supply of AC mains power to the power strip device,
- a low voltage cord extending from the one end surface, from the top surface
or alternatively from one of the side surfaces through a second pull relief bushing
and having at its remote end an exposed light detector, preferably an IR detector
included in a light detector housing for the detection of an optical signal, preferably
an IR signal, generated by a separate remote control unit and for the generation
of a control signal by the detection of the optical signal,
- a set of power outlets constituting switched power outlets and provided at the
top surface and each having a set of terminals including a live terminal and a neutral
terminal, the neutral terminals being connected to the neutral wire of the electrical
- a solenoid relay including a low voltage solenoid having a pair of low voltage
input terminals and an AC switch having a pair of AC output terminals, the AC output
terminals being galvanically separated from the low voltage input terminals, the
live terminals of the set of power outlets being connected to the live wire of the
electric cord through the pair of AC output terminals, and
- an electronic detector circuit included in the housing and connected to the
live wire and the neutral wire of the electrical cord for receiving electrical power,
the electronic detector circuit having a pair of signal input terminals connected
to the low voltage cord for receiving the control signal from the exposed light
detector and a pair of signal output terminals connected to the low voltage input
terminals of the solenoid relay, the electronic detector circuit switching the solenoid
relay on from an off state or, in the alternative switching the solenoid relay off
from an on state through the output of a turn-on signal or, in the alternative,
a turn-off signal, respectively, when receiving the control signal.
According to a particular feature of the electrical power
strip device according to the present invention, the exposed light detector, preferably
the IR detector, is mounted at the remote end of a low voltage cord for allowing
the power strip device to be positioned in a concealed position, e.g. behind a TV
set or a TV furniture or behind a stereo rack or the like where the exposed light
detector may be positioned in a convenient location, e.g. close to the IR detector
of the TV set in question for readily operating the power strip device by directing
the remote control towards the TV set and turning on or turning off the TV set together
with any other equipment such as a DVD player, a VCR, a satellite receiver, a surround
sound amplifier, etc. by directing the remote control unit towards the TV set in
the orientation as if the TV set alone was to be turned on or turned off.
It is to be understood that the user has normally accommodated
a practice of directing the remote control unit towards the TV set for turning on
or turning off the TV set and therefore, provided the power strip device was to
be operated by directing the remote control towards another location, the power
strip device would most likely not be properly operated and could not generally
detect the IR or optical signal generated by the remote control unit and intended
for the switching on or switching off of the TV set together with the other apparatuses
connected to the power strip device according to the present invention.
It is a further distinct feature of the power strip device
according to the present invention that the switching from the low voltage control
side to the high power AC mains supply side is established through a galvanic separation
between the low voltage side and the high voltage side.
In this context, the terms low voltage and high voltage
are to be construed as generic terms representing the non-hazardous low level control
side such as a voltage level of below 40V-50V, e.g. the conventional 5VDC logical
control level of computer equipment and the AC mains voltage level of more than
100V such as the AC mains supply level conventionally used in Europe being 230V/50Hz
and in North America 110V/60Hz and in Japan 110V/50Hz.
Most countries in Europe, in the Far East and also in North
and South America have a standard prescribing the use of a grounded AC power outlet
plug. However, in Denmark, most domestic appliances are not provided with a ground
terminal and most domestic AC power outlets have no ground terminal. In accordance
with the conventional standards such as the international and national standards,
among which several are to be mentioned below, the electrical cord consequently
includes a ground wire and, according to a second and presently preferred embodiment
of the power strip device according to the present invention, the electrical cord
also includes a ground wire and similarly, the power outlets have ground terminals
which are connected to the ground wire of the electrical cord. By the provision
of ground terminals in the AC outlets, a safe grounding of all AC power outlets
is established since the ground terminals of the AC power outlets are permanently
connected to the ground wire of the electrical cord.
For ensuring that the exposed light detector, preferably
the IR detector, may be positioned in the proper position for allowing the user
to direct the remote control unit towards the detector in a convenient manner resembling
the manner in which the TV set or any other home electronic is normally switched
on or off, the low voltage cord preferably has a length of no less than 1 m, preferably
1-2 m, such as approximately 1-1,25 m, 1,25-1,5 m, 1,5-1,75 m, 1,75-2 m, or preferably
approximately 1,25-1,75 m, such as approximately 1,5 m.
The electronic circuitry, in particular the electronic
detection circuit of the power strip device according to the present invention may
be implemented in accordance with any well known electronic principles per se, including
discrete transistors, TTL circuitry, CMOS circuitry. In accordance with a presently
preferred embodiment of the power strip device according to the present invention,
the electronic detection circuit includes a programmable microprocessor and the
light detector is constituted by a phototransistor.
The power strip device may be programmed for the use in
combination with a single control unit exclusively as the microprocessor of the
power strip device may be programmed for the detection of a control signal originating
from an optical signal or an optical code generating by one specific remote control
unit. Alternatively and preferably, the electronic detector circuit includes an
encoder switch for switching the microprocessor from an operational mode into an
encoder mode in which encoder mode the microprocessor stores the control signal
received from the exposed light detector and thereby is programmed for the use in
combination with the remote control unit held by the user.
For ensuring a proper and safe operation of the power strip
device meaning that the power strip device is not unintentionally turned on or off
by the operation of a remote control unit intended to be used in combination with
a different apparatus which is not powered from the power strip device in question,
the microprocessor preferably compares signals received from the exposed light detector
with the control signal stored in the microprocessor for determining whether or
not to respond to the receipt of signal for causing the switching of the solenoid
relay on or off.
For allowing the microprocessor of the electronic detector
circuit of the power strip device according to the present invention to store the
control signal, the electronic detector circuit further and preferably concludes
a storage element such as an E2 PROM, i.e. an Electronic Erasable Programmable
Read Only Memory or any other storage elements well known in the art per se.
In order to obtain the overall goal of reducing the power
consumption by the use of the power strip device rather than having each and every
apparatus powered by a power splitter turned in to standby mode, the electronic
detector circuit preferably includes a low power supply unit for the supply of electrical
power to the electronic circuitry of the electronic detector circuit.
The electrically insulated housing of the power strip device
according to the present invention is preferably made from a plastics material such
as ABS, PP, PC, PV, PE, PVC, Nylon, a combination thereof or any other insulating
plastics material and the housing is preferably made through moulding the housing
in an injection moulding process.
The injection moulded housing may according to a further
advantageous embodiment of the power strip device according to the present invention
be composed of two parts, a bottom part to be snap-fitted or fixed by means of rivets
or bolts and nuts onto a top part comprising the said one end surface, the top surface
and the side surfaces and including a support for the support of a printed circuit
board on which said current amplification circuit is included.
By the provision of the two part housing, the process of
manufacturing the power strip device according to the present invention, in particular
in terms of providing power strip devices for different national or international
standards is simplified as the top housing part is simply injection moulded in accordance
with the national or international standard in question and has the electrical cord
and the low voltage cord mounted together with the electric printed circuit board
constituting a prefabricated unit which is then sealed off by means of the bottom
part. Consequently, the power strip device according to the present invention may
be implemented in accordance with any international or national standards such as
DE/SE/NO, UK, DK, FR, CH, IT, PT, PL, BE, NL, RU, CFA, FI,TW or UL (USA).
As indicated above, the power strip device according to
the present invention is preferably implemented so as to allow all relevant equipment
or all apparatuses to be used in connection with the power strip device to be switched
on and off simultaneously. Consequently, the power outlet was preferably provided
in a number ranging from 2-12, such as 3-8, preferably 3-6.
As stated above, the power strip device according to the
present invention is implemented in accordance with any of the above national or
international standards and for use in connection with 110-230V AC mains supply
appliances such as 110V/60 Hz or 230V/50Hz.
The present invention is now to be further described with
reference to the drawings, in which:
- Fig. 1 is an overall, perspective and schematic view of a first and presently
preferred embodiment of a power strip device according to the present invention
implemented in accordance with a Danish standard called LMJ (Lys Med Jord),
- Fig. 2 is a diagrammatic view illustrating the electronic circuitry of the power
strip device shown in Fig. 1, and
- Fig. 3 is a detailed diagrammatic view of the electronic circuitry of the power
strip device shown in Fig. 1.
In Fig. 1, a power strip device is shown designated the
reference numeral 10 in its entirety. The device is implemented in accordance with
the Danish standard of equipment to be used for mains supply and mains distribution
as the AC outlets of the device are implemented in accordance with the Danish standard
called LMJ (Lys Med Jord). It is to be understood that the power strip device shown
in Fig. 1 is only an example and the technique of providing a power strip device
according to the teachings of the present invention may be implemented in accordance
with any standard such as the Danish standard excluding ground terminals, the Danish
EDB (Elektronisk Data Behandling) standard, the German/Swedish and Norwegian standard,
also known as "Schuko", the standards of other European countries including the
UK, France, Switzerland, Italy, Czechoslovakia, Poland, Portugal and also overseas
standards such as the Japanese, the US or the Australian standards and the international
In more details, the device 10 shown in Fig. 1 comprises
an elongated housing 12 defining a front end from which an AC cord 14 extends through
a first pull release bushing 16 and terminating in an AC plug 18 from which three
pins extend, a first pin 20 constituting a neutral pin, a second pin 22 constituting
a ground pin and a third pin 24 constituting a live pin. From the same front end
of the housing 12, a further cord 26 extends through a second pull release bushing
28, which cord is a low voltage control cord terminating in a housing 30 including
an optical IR sensor 32. Whereas the cord 14 serves for the supply of 230V AC power
to the power strip device 10, the cord 26 serves to supply a control signal by the
detection of an optical or IR signal.
In the housing 12, a total of six AC outlets are provided,
a first one of which is designated the reference numeral 34. The AC power outlets
34 are switched on or off controlled by the control signal supplied to the power
strip device through the cord 26 as will be described in greater details below.
In Fig. 2, the electronic circuitry of the power strip
device 10 is shown. In the upper right hand part of Fig. 2, the plug 18 is shown
having its three pins 20, 22 and 24 extending upwardly. The pins 20, 22 and 24 are
through the plug 18 connected to three wires 40, 42 and 44, respectively, constituting
a neutral wire, a ground wire and a live wire, respectively. As is evident from
Fig. 2, the wires 40 and 42 are connected directly to the switched AC outlets 34.
The live wire 44 is, as is evident from Fig. 2, connected
to a switching on/switching off circuit 50. The circuit 50 is controlled by the
detection of an optical signal or an IR signal generated by a remote central unit
70. The circuitry 50 includes centrally a galvanically separating relay including
a one pole switch 52, which is activated by means of a solenoid coil 60. A first
terminal 54 of the one pole switch 52 is connected to the live wire 44 and, consequently,
connected to the live terminal 24 of the AC plug 18, optionally through a fuse 56,
provided the relevant standard in question prescribes the use of a fuse. A second
terminal 58 of the one pole switch 52 is connected to a switched on/switched off
live wire 62, which is connected to the switched AC power outlets 34.
The low voltage side of the electronic circuitry 50, i.e.
the control side of the solenoid relay includes three main blocks 64, 66 and 68
and a phototransistor 74 and a coding switch 76. The block 64 constitutes a low
power consuming power supply unit for the supply of electrical power to the two
blocks 66 and 68 which constitute a receiver and demodulator block and a microprocessor
controller block, respectively, The receiver and demodulator block 66 is connected
to the phototransistor 74 for receiving an electrical signal as the phototransistor
detects an optical signal or an IR signal generated by means of the remote controller
unit 70. Along with the control signal generated by the receiver and demodulator
block 66, the microprocessor block 68 receives a coding signal provided the coding
switch 76 is activated in which case the microprocessor of the microprocessor controller
block 68 is switched into an encoder mode in which the signal supplied from the
receiver and demodulator block 66 and originating from the optical IR signal generated
by the remote control unit 70 is input to the microprocessor block 68 for encoding
the signal as the control signal, the detection of which is to cause the switching
of the relay 60 for switching on or switching off the AC power outlets 34.
In Fig. 3, the components of the electronic circuitry of
the block 50 is shown in greater details, and in the enclosed list, the components
of the electronic circuitry is presented. No further detailed description of the
electronic circuitry is presented as the diagram is believed to be self-explanatory.
FUSE 5AT 250V
HERO ELECTRONICS LIMITED
The switch 76 shown in Figs. 2 and 3 may be configurated
as a one touch pad which is positioned in the housing 12 in a recess or below a
thin foil housing part. Alternatively, the switch 76 may be included on the printed
circuit board included within the housing of the power strip device 10 and may consequently
only be activated after opening the housing 12. The power strip device 10 in the
embodiment described, in which the switch 76 is not assessable from the exterior
relative to the housing 12 is dedicated and encoded for a specific type of remote
control units or a specific brand of electronic equipment.
Although the present invention has been described above
with reference to a specific and presently preferred embodiment of the power strip
device according to the present invention, numerous modifications, as already mentioned
above, will be obvious to a person having ordinary skill in the art, as the power
strip device may be modified for complying with a specific national or international
AC mains supply standard and further the number of switched AC power outlets may
be varied from e.g. three to a number exceeding the number shown in Fig. 1. All
such modifications are to be considered part of the present invention as defined
in the appending claims.