GB2195441A - In-line proximity switch - Google Patents

In-line proximity switch Download PDF

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Publication number
GB2195441A
GB2195441A GB08719808A GB8719808A GB2195441A GB 2195441 A GB2195441 A GB 2195441A GB 08719808 A GB08719808 A GB 08719808A GB 8719808 A GB8719808 A GB 8719808A GB 2195441 A GB2195441 A GB 2195441A
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GB
United Kingdom
Prior art keywords
switch
line
switching
switch according
current
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB08719808A
Other versions
GB8719808D0 (en
Inventor
Gordon Stukeley Ritchie
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB868621209A external-priority patent/GB8621209D0/en
Priority claimed from GB878704151A external-priority patent/GB8704151D0/en
Application filed by Individual filed Critical Individual
Priority to GB08719808A priority Critical patent/GB2195441A/en
Publication of GB8719808D0 publication Critical patent/GB8719808D0/en
Publication of GB2195441A publication Critical patent/GB2195441A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K17/00Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/56Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
    • H03K17/72Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices having more than two PN junctions; having more than three electrodes; having more than one electrode connected to the same conductivity region
    • H03K17/725Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices having more than two PN junctions; having more than three electrodes; having more than one electrode connected to the same conductivity region for ac voltages or currents
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K17/00Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/94Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
    • H03K17/941Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated using an optical detector
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B47/00Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
    • H05B47/10Controlling the light source
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B47/00Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
    • H05B47/10Controlling the light source
    • H05B47/105Controlling the light source in response to determined parameters
    • H05B47/115Controlling the light source in response to determined parameters by determining the presence or movement of objects or living beings
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40Control techniques providing energy savings, e.g. smart controller or presence detection

Landscapes

  • Electronic Switches (AREA)

Abstract

A proximity switch e.g. for a domestic a.c. supply is connected in-line e.g. in the live line of the supply between live and switch live terminals. No direct connection is made to the neutral line. Switching is performed by a triac which receives a gate input from a control circuit K that includes an optical proximity switch. The control circuit K has a power supply comprising a charge storage capacitor C1 that is charged from the live terminal through a first impedance I1 and a unidirectional first path through diode D1 when the triac is conductive. When the triac is switched to a non-conductive state, the capacitor C1 is charged from the switch live terminal through a second unidirectional path including diode D2 and a second impedance I2. The proximity switch may be replaced by a touch switch or a dimmer switch. <IMAGE>

Description

SPECIFICATION In-line switch FIELD OF THE INVENTION This invention relates to an electrical switch suitable for example for mains powered electric lighting.
BACKGROUND TO THE INVENTION Touch sensitive electrical switches are known for switching an a.c. domestic mains supply. Such switches have a pair of electrodes which in use are bridged by application of a finger of the operator, to cause an electrical switching action. Such touch sensitive switches have been configured to operate "inline". This means that the switch is connected in a break in e.g. the live line of an a.c. supply between resulting terminals which are known as the line and switch line terminals, without connection to the other a.c. supply line e.g. the neutral line. Thus when connected in the live line, the line and switch line terminals may be termed the live and switch live terminals.This can be seen more clearly from Figure 1, wherein by way of example Figure 1(a) shows an unswitched a.c. supply to a lamp, Figure 1(b) shows schematically an "inline" switch SW connected in a single one of the a.c. supply lines (the live line) between line L and switch line SWL terminals, whereas Figures 1(c) and 1(d) show switches which are not "in-line" because they are connected to both the line and neutral a.c. lines. Because the touch sensitive switches can be configured to operate "in-line" they can be used in homes to replace conventional mechanical light switches which are usually connected in-line.
It is also known to provide a proximity switch for mains powered lighting, which is operated by bringing a suitable target, for example a hand, sufficiently close to the switch (but not necessarily touching it). Typically the switch will operate when the hand is brought within 5 to 100 my of the switch.
However, due to the more complex switching arrangements used in proximity switches it has been necessary to provide such arrangements with a smooth continuous power supply derived from the a.c supply, which hitherto has required connections to both the live and neutral supply lines. Thus hitherto, proximity switches have not been suitable for in-line use, with the disadvantage that they cannot be used as replacements for conventional domestic mechanical light switches.
Known in-line switches (e.g. touch switches) which employ electronic switching elements include a coil in series with the switching element e.g. a triac, and function by conduction angle controlled mains frequency switching.
When such switches are "on" or "closed" they are in fact off for a given minimum, nonzero fraction of every mains half cycle. A typical maximum conduction angle is 1500 (rather than 1800). In this way the mean voltage across the coil is some non-zero minimum value big enough to provide continuous power for the electronic switching element and associated circuitry. Such power supplies are therefore switching power supplies, and produce RFI which has to be suppressed in ac 'cordance with various engineering standards such as BS800.
SUMMARY OF THE INVENTION Broadly stated, the present invention provides an in-line proximity switch.
More particularly the invention provides an in-line proximity switch for connection in an electrical circuit including a load and first and second current supply conductors connected to the load, the switch comprising: line and switch line terminals, semiconductor switching means operative to switch current flow between the terminals, and control means including a proximity switching device operative in response to a target being placed proximate to but not actually touching the device, and drive means responsive to operation of the proximity switching device for operating the semiconductor switching means, wherein said switch is arranged to be connected solely into one of said current supply conductors by means of said line and switch line terminals.
Further, the invention provides a switch which employs an in-line power supply that is an improvement over known in-line power supplies in that it is not a switching power supply and so does not produce appreciate RFI.
Accordingly, the invention provides an electrical switch including semiconductor switching means connected for switching a current supply line between line and switched line terminals, the switching means being powered from a power supply including charge storage means, and means for establishing first and second charging current supply paths extending respectively from the line and switched line terminals to the charge storage means.
A switch according to the invention with its improved power supply can be driven by a proximity switching device and operate in-line, or can be driven by other switching control devices such as dimmer controls or touch sensitive switches.
BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention be more fully understood an embodiment thereof will now be described with reference to the accom panying drawings hereunder whereof; Figure 1 is a schematic diagram of circuits showing different lamp and switch connections as discussed hereinbefore Figure 2 is a schematic circuit diagram of a power supply used in a switch according to the invention Figure 3 is a schematic circuit diagram of a more specific example of a power supply for use in a switch according to the invention Figure 4 is a circuit diagram of a preferred non-switching power supply for an in-line proximity switch.
Figure 5 is a schematic block diagram of a suitable control circuit for the preferred radiation reflective in-line proximity switch.
Figure 6 is a detailed circuit diagram of a preferred control circuit Figure 7 shows an enhanced dual power supply for an improved in-line proximity switch.
Figure 8 shows two designs for face plates for wall mounted in-line proximity switches, being used as standard light switch or touch switch or dimmer replacements.
DESCRIPTION OF EMBODIMENTS A suitable non-switching power supply is now described with reference to Figure 2, which is a block schematic diagram of an inline proximity switch.
Referring to Figure 2, a first impedence 11 and a switch element e.g. a triac S are connected in series between the live and switch live terminals L and SWL in the manner shown schematically in Figure 1(b). The potential of the connection between impedence Il and element S is chosen to be ground for convenience, and is called G. The switch element is driven by a control circuit K that conveniently includes a proximity switch as will be described hereinafter. The circuit K is powered from a power supply that includes a.
capacitor C1 provided between G and the point V to store energy. A first current path (preferably unidirectional) P1 is provided from the live terminal to V, and a second current path P2 (preferably unidirectionalS is provided between the switch live terminal and V through a second impedance 12. A feature of this power supply and switch element S is that the two terminals may be reversed in mains systems without impairing its function, because of the symmetry of the a.c. supply.
When the switch element S is closed i.e.
conductive, current flows through the first impedence 11 generating a voltage across it.
This voltage drives current through the first current path P1 to charge the reservoir capacitor C1. When the switch element is open i.e.
non-conductive, neglible current flows through the first impedence 11, and hence neglible voltage is generated across it. Since the switch is connected in an a.c. circuit through a load e.g. a lamp as shown in Figure 1(b), current instead flows along the second current path P2 through the second impedence 12, thereby charging the capacitor C1. C1 then provides the required energy for the control circuit K which drives the switch S.
Figure 3 shows a particular example of Figure 2 wherein a diode D1 provides a unidirectional first current path and a diode D2 provides a unidirectional second current path through the second impedence 12. Both paths thereby charge the capacitor C1 so that V is at a negative potential with respect to G.
When the switching element S is a triac, drive is more efficient with a negative voltage powered circuit K.
Referring to Figure 4, the first impedence 11 of Figure 3 is implemented by a five series diodes D3 in inverse parallel with D4. This combination makes a sort of zener diode at 3 volts. When the triac T is on, the live terminal is-3 volts with respect to G (at zero volts) every other half cycle, and C1 is charged through D3 to -2.4 volts at V. When the triac is off, the switch live terminal sees (through the neutral line and the circuit load-not shown) approximately 240 V ac with respect to G and so the second current path comprising R, D4, allows C1 to be charged to a negative voltage limited by a zener diode Z.Capacitor C2 is included for dv/dt limiting across the triac T and spike supression, and small inductance coil L is included as a dl/dt limiter.
Thus, in use the control circuit K can be used to switch the conductive state of the triac between the conductive and non-conductive conditions. The arrangement has the advantage that a substantially continuous charging current is supplied to the capacitor C1 through the first and second paths P1, P2 irrespective of the switching state of triac T, to provide for continuous operation of the control circuit K, with consequential reliable triggering of the triac T. The large inductive coil used in the prior art in series with the triac can be dispensed with and replaced by the essentially resistive diode arrangement D3, D4 because there is neglible RF1 to be suppressed.
The control circuit K in this embodiment of the invention comprises a proximity switch powered from the continuous supply developed across capacitor C1. An example of the proximity switch is shown in block diagrammatic form in Figure 5, and operates by detecting radiation reflected by a target such as a hand of an operator.
An oscillator 10, which is preferably of low duty cycle and typically at 10khz, drives a radiation emitter 11 preferably including an an infra-red LED. A detector 12 comprises a photodiode which is connected to a decoder 13 that picks out 10 khz components from detected ambient levels of light. A Schmidt trigger 14 driven by decoder 13 toggles a bistable latch 15 that by means of drive circuit 16 operates the triac T (Figure 4) such that each time the hand is brought within a 5-100 millimetres of the emitter detector pair 11, 12 (which are mounted adjacent to one another) the switch 16 changes state. The use of a Schmidt trigger 14 inhibits multiple switching being produced by one hand movement.
Figure 6 shows in more detail the circuit diagram of the proximity switch and corresponds to the circuit elements 10 to 17 shown in Figure 5. The detector 12 comprises a photodiode S the impedance of which varies with incident light intensity, causing a voltage signal across R2 which is fed to the decoder 13 in the form of a high pass filter C3, R3 that rejects ambient light signals (especially 50-60 hz variations). The resulting filtered signal is amplified by an op amp (a) (preferably ground sensing) and then passed through a high pass filter C4, R4. An op amp (b) amplifies the further filtered signal and a peak detector with low droop D5, R5, C5 converts the spikes received by photodiode S to a fairly smooth DC signal.
The circuitry around op amp (c) provides the oscillator 10 with a low duty cycle (any frequency significantly above 50-60 Hz will work). The emitter 11 comprises an infra-red LED E that emits spikes of light at the oscillator frequency. Spikes are employed for low power consumption.
An op amp (d) forms the Schmidt trigger 14. A transistor Q1 speeds up the transition time of the trigger to a level acceptable to the toggling bistable latch 15 here implemented using a D-type flip-flop (e). The output from the latch (e) switches transistor Q2 which acts as the switch drive circuit 16 and drives triac gate terminal 17. The triac gate terminal 17 can be used to control the triac T shown in Figure 4 or in Figure 7.
Figure 7 shows a dual non-switching power supply which may be used to enhance the performance of the in-line proximity switch. In Figure 7 DIA and RIA are the first and second impedances for an "A" power supply respectively and similarly DIB and RIB are for a "B" supply. The "A" supply charges capacitor C6 and can be used to power the control circuit elements - 10-15 but not the triac gate drive circuit 16 whereas the "B" supply charges capacitor C7 and can be used to supply the triac gate drive circuit 16 and triac gate 17 with current.In this way if the triac is asked to turn on when insufficient charge or voltage is present in C7 for this to occur, then the triac gate supply will fail but the control circuit supply will still be functioning, thereby allowing the circuit to turn off the triac gate drive, so that C7 can be recharged by the second current path P2. Then a turn on can be reattempted.
This problem arises because the second current path P2 may not provide enough current to drive the triac gate 17 when the triac T is on, whereas the first current path can easily provide such current. As a result if the triac T is asked to turn on, then for a few milliseconds, whilst the triac changes state, the second current path P2 will be trying to drive the gate with a current which exceeds its capabilities and so the capacitor C7 may run out of charge before turn on is affected in which case the triac will remain off with the triac gate drive on and the gate drive power supply will fail.
Figure 8 shows two suitable face plate designs for wall mounted in-line electric light proximity switches. The faceplate 18 shown in Figure 8(a) mimics a standard light switch with the rocker replaced by an infra-red transmissive cover 19 behind which the emitter and detector are arranged. The faceplate 18 of Figure 8(b) has two infra-red transmitting covers, one for the emitter and one for the detector, both of which are mounted behind said covers.
Various modifications falling within the scope of the invention are possible. For example, whilst hereinbefore the control circuit K is described as including a proximity switch as described with reference to Figures 5 and 6, it would be possible instead to include a switching control device in the form of a dimmer control or a touch sensitive switching device.

Claims (20)

1. An in-line proximity switch for an a.c.
mains supply.
2. An in-line proximity switch for connection in an electrical circuit including a load and first and second current supply conductors connected to the load, the switch comprising: line and switch line terminals, semiconductor switching means operative to switch current flow between the terminals, and control means including a proximity switching device operative in response to a target being placed proximate to be not actually touching the device, and drive means responsive to operation of the proximity switching device for operating the semiconductor switching means, wherein said switch is arranged to be connected solely into one of said current supply donductors by means of said line and switch line terminals.
3. A switch according to claim 2 including power supply means for driving said control circuit means, including: charge storage means; means providing a first charging current path from said line terminal to said charge storage means for charging said storage means when said semiconductor switching means is in a first conductive condition, and means providing a second charging current path from said switch line terminal for charging said storage means when said semiconductor switching means is in a second different conductive condition.
4. A switch according to claim 3 wherein said first and second paths each include respective diode means to render the paths unidirectionally conductive.
5. A switch according to claim 3 or 4 including means for limiting the maximum voltage established across said charging current in said first and second paths.
6. A switch according to claim 5 wherein said charge storage means comprises a capacitor and said voltage limiting means comprises a zener diode.
7. A switch according to any one of claims 3 to 6 including first impedance means connected in series between said live terminal and said semiconductor switching means, said charge storage means having a first connection made to the series connection of the first impedance means and the switching means, and a second connection to said first and second charging current paths, said second path including second impedance means.
8. A switch according to claim 7 wherein said first impedance means comprises an array of diodes.
9. A switch according to claim 7 or 8 wherein said second impedance means comprises a resistor.
10. A switch according to any one of claims 3 to 9 and including a first and a second of said power supply means arranged to power said proximity switching device and said drive means respectively.
11. A switch according to any one of claims 2 to 10 wherein said semiconductor switching means comprises a triac.
12. A switch according to any one of claims 2 to 11 wherein said proximity switching device comprises a radiation emitter for emitting radiation of a predetermined characteristic, a radiation detector and decoder means for providing an output indicative of whether radiation detected by the detector contains the characteristic of the radiation emitted by the emitter.
13. A switch according to claim 12 including a Schmidt trigger responsive to changes in the output of the decoder means, and a latch driven by the Schmidt trigger, said drive means being driven by the latch.
14. A switch according to claim 12 or 13 wherein said radiation emitter comprises an infra-red LED driven by an oscillator of low duty cycle to impart said predetermined characteristic to the emitted radiation.
15. An electrical switch including semiconductor switching means connected for switching a current supply line between line and switched line terminals, the switching means being powered from a power supply including.
charge storage means, and means for establishing first and second charging current supply paths extending respectively from the line and switched line terminals to the charge storage means.
16. An electrical switch comprises: line and switch line terminals; semiconductor switching means operative to switch current flow between the terminals, control circuit means including an electrical switching control device, and drive means responsive to the switching state of the switching control device for operating the semiconductor switching means, and power supply means for driving said control circuit means and including charge storage means, means providing a first current charging path from said line terminal to said charge storage means for charging said storage means when the semiconductor switching means is in a first conductive condition, and means providing a second current charging path from said switch line terminal for charging said storage means when said semiconductor means is in a second different conductive condition.
17. A switch according to claim 16 wherein said switching control device comprises a touch sensitive device.
18. A switch according to claim 16 wherein switching controls device comprises a dimmer control.
19. A switch according to claim 16 wherein said line and switch line terminals are the sole connections thereof, for connection into one of a plurality of current supply conductors that supply current through a load.
20. An electrical switch substantially as hereinbefore described with reference to Figures 2 to 6 as modified by Figure 7 of the accompanying drawings.
GB08719808A 1986-09-02 1987-08-21 In-line proximity switch Withdrawn GB2195441A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB08719808A GB2195441A (en) 1986-09-02 1987-08-21 In-line proximity switch

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB868621209A GB8621209D0 (en) 1986-09-02 1986-09-02 Electrical switch
GB878704151A GB8704151D0 (en) 1987-02-23 1987-02-23 In-line proximity switch
GB08719808A GB2195441A (en) 1986-09-02 1987-08-21 In-line proximity switch

Publications (2)

Publication Number Publication Date
GB8719808D0 GB8719808D0 (en) 1987-09-30
GB2195441A true GB2195441A (en) 1988-04-07

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Family Applications (1)

Application Number Title Priority Date Filing Date
GB08719808A Withdrawn GB2195441A (en) 1986-09-02 1987-08-21 In-line proximity switch

Country Status (1)

Country Link
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2291289A (en) * 1994-07-06 1996-01-17 Robert Ian Murrells Non-contact incandescent lamp switching and dimming device
EP0722262A2 (en) * 1995-01-13 1996-07-17 Pierre Saint-Cyr Optically controlled dimmer-type device
DE19632129A1 (en) * 1996-08-09 1998-02-12 Insta Elektro Gmbh & Co Kg Power regulator power supply circuit
NL1007130C2 (en) * 1997-09-26 1999-03-29 Thyssen De Reus Bv Safety switch.
DE19807517A1 (en) * 1998-02-21 1999-08-26 Insta Elektro Gmbh & Co Kg Electronic two wire switch for controlling electronic loads e.g. incandescent lamps
DE10017432A1 (en) * 2000-04-07 2001-10-11 Kopp Heinrich Ag Dimmer switch arrangement e.g. for lighting systems, includes monitor for tracking the dimmer supply voltage supplied from the voltage supply circuit
DE10025368A1 (en) * 2000-05-23 2001-12-06 Kopp Heinrich Ag dimmer
GB2390892A (en) * 2002-03-14 2004-01-21 Matthew Paul Michael Swipe switch
EP1672796A3 (en) * 2004-12-14 2007-03-14 Sen-Tien Shih Optical proximity switch
US8870443B2 (en) 2008-04-17 2014-10-28 Sartorius Stedim Biotech Gmbh Flexible pouch with a mixing apparatus

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1423311A (en) * 1972-01-22 1976-02-04 Buck R Electronic proximity switching unit
GB1480613A (en) * 1973-06-14 1977-07-20 Buck R Electronic switching arrangement
GB1490221A (en) * 1973-11-13 1977-10-26 Buck R Electronic monitoring apparatus which preferably works without being touched
GB1538719A (en) * 1976-03-30 1979-01-24 Buck R Electronic switching device
GB1550303A (en) * 1976-04-13 1979-08-08 Buck R Electronic switching device
GB1564870A (en) * 1976-04-15 1980-04-16 Buck R Electronic switching device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1423311A (en) * 1972-01-22 1976-02-04 Buck R Electronic proximity switching unit
GB1480613A (en) * 1973-06-14 1977-07-20 Buck R Electronic switching arrangement
GB1490221A (en) * 1973-11-13 1977-10-26 Buck R Electronic monitoring apparatus which preferably works without being touched
GB1538719A (en) * 1976-03-30 1979-01-24 Buck R Electronic switching device
GB1550303A (en) * 1976-04-13 1979-08-08 Buck R Electronic switching device
GB1564870A (en) * 1976-04-15 1980-04-16 Buck R Electronic switching device

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2291289A (en) * 1994-07-06 1996-01-17 Robert Ian Murrells Non-contact incandescent lamp switching and dimming device
EP0722262A2 (en) * 1995-01-13 1996-07-17 Pierre Saint-Cyr Optically controlled dimmer-type device
EP0722262A3 (en) * 1995-01-13 1996-08-07 Saint Cyr Pierre
DE19632129A1 (en) * 1996-08-09 1998-02-12 Insta Elektro Gmbh & Co Kg Power regulator power supply circuit
NL1007130C2 (en) * 1997-09-26 1999-03-29 Thyssen De Reus Bv Safety switch.
EP0905901A1 (en) * 1997-09-26 1999-03-31 Thyssen De Reus B.V. Safety switch
DE19807517A1 (en) * 1998-02-21 1999-08-26 Insta Elektro Gmbh & Co Kg Electronic two wire switch for controlling electronic loads e.g. incandescent lamps
DE10017432A1 (en) * 2000-04-07 2001-10-11 Kopp Heinrich Ag Dimmer switch arrangement e.g. for lighting systems, includes monitor for tracking the dimmer supply voltage supplied from the voltage supply circuit
DE10025368A1 (en) * 2000-05-23 2001-12-06 Kopp Heinrich Ag dimmer
GB2390892A (en) * 2002-03-14 2004-01-21 Matthew Paul Michael Swipe switch
EP1672796A3 (en) * 2004-12-14 2007-03-14 Sen-Tien Shih Optical proximity switch
US8870443B2 (en) 2008-04-17 2014-10-28 Sartorius Stedim Biotech Gmbh Flexible pouch with a mixing apparatus

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