WO1992016881A1

WO1992016881A1 - Electrical timer device

Info

Publication number: WO1992016881A1
Application number: PCT/AU1992/000129
Authority: WO
Inventors: Narelle Kai De Boos; James Christian Mitchell
Original assignee: Narelle Kai De Boos
Priority date: 1991-03-25
Filing date: 1992-03-25
Publication date: 1992-10-01

Abstract

An electrical timer device (28) for installation in a building (26) for regulating the supply of electricity to electrical wiring (30, 31) of the building. The timer device includes timing means to switch on or off the supply of electricity to the electrical wiring at intervals during the day. The timer device, when installed, may visually appear to be a conventional wall mounted switch for controlling, for example, overhead lighting (32).

Description

ELECTRICAL TIMER DEVICE

The present invention relates to an electrical timer device. More particularly, the invention relates to an electrical timer device which is adapted to control the supply of electricity to electrical wiring of a building.

Electrical timer devices may be arranged for control of the supply of electrical current from a mains electrical outlet socket to an electrical appliance attached thereto. Such electrical timer devices may be provided with plug pins suitable for insertion into a mains electrical outlet socket for connection to the mains electricity supply of a building, and a controlled outlet socket suitable to receive the plug pins of an electrical appliance. The electrical timer device may be programmable, either electronically or mechanically, with switch-on and switch-off times. When the timer within the electrical timer device corresponds to a programmed switch-on time, the device may act to provide supply of electrical current to an electrical appliance attached thereto via the controlled outlet socket by electrically connecting the electrical contacts of the controlled outlet socket to the pins inserted in the mains socket. The electrical appliance may remain supplied with electricity until the timer corresponds to a pre-programmed switch-off time, at which the electrical connection between the controlled outlet socket and the mains socket plug pins is broken. Using such a device, an electrical appliance may be switched on and off at various pre-programmed times of the dav. _ -. _

Such an electrical timer device may be used for the purpose of deterring household burglaries. An electric lamp may be connected to the household mains electrical supply via an electrical timer device pre-programmed to supply the electric lamp with electrical power during predetermined periods of the day and night. If the household residents are absent from the house during an extended period of time, for example on holiday, the switching on and off of the lamp connected to the electrical timer device may create the illusion of people present in the house, thus to deter a potential burglar.

Electrical timer devices as above described require the use of an accessible electrical mains outlet socket, and thus arc only able to control the electrical supply to lamps which are able to be connected to such an electrical socket. This may have a twofold disadvantage in burglary prevention, since it may be possible for a potential burglar to view, through a window, the connection of the electrical timer device, and also ascertain that electric lamps installed in lighting fixtures of the house are not in use.

In accordance with the present invention there is provided an electrical timer device for installation in a building, comprising switching means in use regulating the supply of electricity to electrical wiring of said building, and timer means which in use controls said switching means to regulate said supply of electricity over a period of time.

Preferably the switching means regulates the supply of electricity by, in use, switching on or off the supply of electrical current to said electrical wiring.

Preferably said timer means controls the switching means to switch the supply of electrical current on or off at predetermined times.

Preferably the switching means of the timer device includes terminals adapted for direct connection to wires of said electrical wiring. Preferably also said timer device is adapted for installation in a wall of said building.

Embodiments of the present invention will hereinafter be described, by way of example only, with reference to the accompanying drawings, wherein:

Figure 1 shows an arrangement of an electrical timer device of the prior art;

Figure 2 shows a variation of the prior art electrical timer device;

Figure 3 shows a generalised arrangement of the electrical timer device according to embodiments of the present invention, when installed;

Figure 4 is a perspective view of an electrical timer device according to a first embodiment of the present invention;

Figure 5 shows a front panel of the first embodiment;

Figure 6 shows a front panel of a second embodiment of the present invention; Figure 7 is a perspective view of a third embodiment, being a modification of the first embodiment of the present invention;

Figure 8 is a simplified circuit diagram of the first embodiment;

Figures 9 and 10 are partial cross-sectional views showing means by which embodiments of the invention may be, in use, installed; Figures 11 and 12 are front perspective views of modifications of a front portion of the embodiments; and

Figure 13 is a rear view of a switching unit in accordance with embodiments of the invention, showing an example of contact terminals for connection of wires thereto.

Throughout the detailed description of embodiments of the present invention which follows, like reference numerals denote similar items in each Figure.

Figure 1 shows a mechanically programmable electrical timer device 2 according to the prior art. The device 2 is provided with a mechanical programmable timer 14 and a standard configuration three pin controlled electrical outlet socket 10. The device 2 is also provided with a standard three-pin electrical plug (not shown) on an opposed face to the controlled electrical socket 10. The pins of the electrical device 2, in use, are pluggable into a household mains electrical socket 6, contained in a wall plate 4, electrical connection with which provides power to the timer 14 and, in use, the controlled socket 10. In use of the device 2 an electrical appliance 16, such as an electric lamp, is able to be plugged into the controlled outlet socket 10 by means of electrical plug pins 12.

Electrical connections within the device 2 are provided to electrically couple the earth and neutral plug pins (not shown) of the device 2 directly to the earth and neutral electrical contacts of the controlled outlet socket 10. A relay is provided within the device 2 to enable selective connection between the active plug pin (not shown) of the device to the active electrical contacts of the socket 10. The relay is in turn controlled by the programmable timer 14. The timer 14 comprises a circular spindle 13 along the circumferential edge of which may be located programming projections 11. During operation the timer spindle 13 carrying the programming projections 11 rotates at a rate of one complete rotation every 24 hours. As the spindle rotates, successive programming projections 11 bear against a switch projection 15, which causes the relay to connect or disconnect the active contacts of control socket 10 to the active plug pin of the device 2.

Figure 2 shows an electronically programmable electrical timer device 18 of the prior art. The device 18 operates in a manner similar to the mechanically programmable device 2, described in relation to Figure 1, but having an electronic timer rather than a mechanical rotating timer. The electronic programmable timer of the device 18 would typically include a digital display 22 and a number of programming push buttons 20. Switch-on and switch-off times may be entered and stored in the digital timer, for each day of the week^', using the programming push buttons 20. In the manner described above, the electrical timer device 18 is, in use, plugged into a domestic mains power outlet socket 6 (Figure 1), and an appliance to be controlled is plugged into the controlled outlet socket 10 of the device 18. Figure 3 shows diagrammatically an arrangement which may be utilised by embodiments of the present invention. The figure shows a portion of a room, for example in a residential building, having overhead electric lighting 32 mounted on a ceiling 27. The overhead lighting 32 is supplied with electricity from the mains building wiring 24 and 25 (shown in dashed lines), which wiring runs beneath a floor 29 of the room and behind a wall 26 to a switching unit 28. Connecting wires 30, 31 run from the switching unit 28 behind the wall panel 26 and above the ceiling 27 to the overhead lighting 32. The supply of electricity from the mains wiring 24 and 25 to the lighting 32 may be controlled by a switch 34 of the wall mounted switching unit 28 constructed in accordance with the present invention. Electrical current to overhead lights of a building are conventionally controlled by wall mounted switches, and in this way, embodiments of the present invention may visually appear to be conventional wall mounted overhead lighting switches.

A perspective view of a first embodiment of the present invention is shown in

Figure 4 as switching unit 28. The unit 28 is of a generally rectangular box shape with a protruding front rim 70 extending around the edge of its front face. The face bordered by the rim 70 comprises a substantially flat front cover plate 58 having a generally central plate aperture 60, and is pivotally movable about its lower edge by virtue of hinges 56, allowing the front cover plate 58 to swivel about its lower edge to the position shown in Figure 4 wherein a front panel 36, also bordered by front rim 70, of the switching unit is exposed. When the front cover plate 58 is in its closed position a projection 66 of the front cover plate 58 engages with a latch 68 located on the front panel 36 to secure the plate 58 in its closed position. Whilst in the closed position the apeπure 60 of the front cover plate 58 surrounds a switch mechanism 34 which projects from the front panel 36. A spring biasing mechanism 62 may also be provided to engage lugs 64 located on the front panel 36 and the plate 58 to resiliency bias the plate 58 towards its open or closed positions. Located on the front panel 36 are control push button 41, programming push buttons 40 and a digital display 38.

When the switching unit 28 is installed for use in a wall panel 26, as shown in Figure 3, the front rim 70 projects to the exterior of the wall whilst a rear casing 72 of the switching unit 28, rearward of the rim 70, projects to the interior of the wall. During normal operation, the plate 58 is in its closed position substantially in the plane of the rim 70, with the projection 66 engaged with latch 68. With the plate 58 in the closed position a portion of switch 34 projects through aperture 60 of the plate 58 to enable the switch to be moved between on and off positions, whilst the remainder of front panel 36, hinges 56 and latch 68 are obscured by the plate 58. In the embodiments described herein, the front rim 70, front cover plate 58, front panel 36 and rear casing 72 are formed from a plastics material.

Figures 5 and 6 show possible arrangements of controls on the front panel 36 of embodiments of the invention. The arrangement shown in Figure 5 corresponds to a switching unit 28 in accordance with the first embodiment as shown in Figure 4, incorporating an electronic programmable digital timer similar to that used in the device 18 shown in Figure 2. As shown in both Figures 4 and 5, the front panel 36 is arranged with a switch 34, located in a generally central position on panel 36, a projecting portion of which switch 34 is movcable between upper and lower switch positions. At the upper left portion _. of panel 36 is located a digital display 38, such as an LED or liquid crystal numeric or alpha-numeric display. During operation the digital display 38 provides the current time of the timer circuit, and during programming of the device provides prompting and visual feedback of the programming sequence and switch-on/off times. To facilitate programming of the timer there are also provided programming push-buttons 40, located on the panel 36 below the digital display 38. Programming buttons 40 may be provided for the selection of days of the week, hours and minutes, as well as for selection of the programming operation and any other functions which may be required, such as a "reset" function. Also provided on the front panel 36 is a control push button 41 which switches control of electrical current between the timer and the manual switch 34.

The arrangement shown in Figure 6 is typical for a switching unit 28 constructed in accordance with a second embodiment of the present invention, which utilises a mechanical timer 14 similar to the timer 14 of electrical timer device 2 shown in Figure 1. In the arrangement shown, the timer spindle 13 encircles the centrally located manual switch 34 on the front panel 36 to enable a compact arrangement. A power indicator 44 is provided on the panel 36 adjacent the switching projection 15 of the mechanical timer 14 to indicate the status of the switching device. A control switch 41 is provided to allow switching of control of electrical current between the timer 14 and the manual switch 34.

Figure 7 shows a third embodiment of the invention. The switching unit 28 of the third embodiment operates, in most respects, in the same manner as the first embodiment switching unit. The third embodiment, however, provides for a battery backup electrical system for the electronic timer circuitry. The battery backup is facilitated by the provision of a rectangular battery recess cavity 96 in front panel 36 on the opposite side of the centrally located switch 34 from the display 38 and programming push buttons 40, said recess cavity 96 being of a size adapted to receive a backup battery 94. Typically, rcsiliently sprung battery contact terminals would be provided at opposing ends of the battery recess 96, to make electrical contact with electrical terminals on opposed ends of the backup battery 94, and secure the battery 94 within the battery recess 96.

Figure 8 shows a block diagram of the operational components of an electronic programmable timer 91 and switching circuitry 93 which may be utilised in embodiments of the present invention. The electronic programmable timer portion 91 comprises timer and control circuitry 84, programming push buttons 40 and digital display 38. The timer and control circuitry 84 includes an electronic time clock, memory for storing programmed switch-on and switch-off times, programming circuitry necessary to decode key presses from the programming push buttons 40 and store the corresponding switch-on and switch-off times in the memory, and driving circuitry for the digital display 38. The timer and control circuitry 84 also provides a comparator circuit to compare the output of the electronic time clock with the stored switch-on and switch-off times, and a digital output control line 90 which provides the input for the switching circuitry 93. Certain embodiments of the invention also provide a battery backup 95, deriving power from backup battery 94 (Figure 7). the battery backup 95 may continuously provide power to the electronic programmable timer portion 91 or, alternatively, may only provide power to the electronic programmable timer 91 in the event of a mains power failure, normal power to the electronic programmable timer 91 being provided from the mains electricity via power conditioning circuitry. The switching circuitry 93 comprises a driver amplifier 88, a timer control switch 41, a relay switch 82 and a manual on/off switch 34. The driver amplifier 88 receives input 90 from the timer and control circuitry 84 and passes the amplified signal to timer control switch 41. The timer control switch 41 is a push button type switch which is able to be controlled by the user (see Figures 4 and 7). Control switch 41 controls the output of the electronic programmable timer 91 such that, when the switch 41 is closed the driver amplifier 88 is able to energise relay coil 92 to control the relay switch 82. When the switch 41 is open the electronic programmable timer 91 continues to operate, however, it is not able to control the flow of electrical current in the active line 25. Relay switch 82 is of the normally- closed variety such that, if switch 41 is in the open position and relay coil 92 is not energised, then relay switch 82 is in the closed position, thus allowing the flow of electrical current in active line 25 to be controlled by the manual switch 34.

When installed, embodiments of the invention such as shown in Figures 4 and 7 will ordinarily be used to control some type of overhead light. The switching unit 28 will be installed in a cavity in a wall panel 26 with the rear casing 72 extending into the wall behind the wall panel 26, and the front cover plate 58 and front rim 70 projecting outward slightly from the wall panel 26. Wires connected to mains electricity couple to active and neutral input terminals 150, 151 (Figure 8), and wires connected to the controlled overhead light 32 couple to active and neutral output terminals 152, 153. The input and output terminals 150, 151, 152, 153 are preferably screw contact type terminals adapted to receive and make electrical connection with the bared end of an insulated wire, however many types of terminals may be used for this purpose. Input terminals 150, 151 would ordinarily be located in a lower portion of the rear casing 72 such that contact may easily be made with mains electrical wires 24, 25 extending from the floor 29 behind the wall panel 26 (Figure 3). Similarly, output terminals 152, 153 would ordinarily be located in an upper portion of the rear casing 72 to allow easy contact with wires 30, 31 (Figure 3) which connect to overhead light 32. Figure 13 shows a rear view of the rear casing 72 of a switching unit 28 having terminal contacts as described above. Mains wires 25 and 25 from the mains building electrical wiring connect to terminals 151 and 150 located in the lower rear edge of casing 72. The connecting wires 30 and 31 connect to terminals 152 and 153 located in the upper rear edge of casing 72. The connections within the switching unit (shown in dashed lines) are in accordance with the switching circuitry 93 shown in Figure 8.

In a household application the switching unit 28 will, for the majority of the time, operate as a standard wall mounted light switch. In this situation switch 41 is in its open position and relay switch 82 is in its normally closed position, allowing the flow of electrical current from the mains electrical wires 24, 25 and terminals 150,

151 to the controlled light 32 via terminals 152, 153 and connecting wires 30, 31 to be controlled solely by switch 34. When the electronic programmable timer 91 is required to control the overhead light 32, the timer and control circuitry 84 must first be programmed using programming push buttons 40 and digital display 38. To activate the timer control switches 34 and 41 are placed in their closed positions, allowing the flow of electrical current between mains input terminal 150 and output terminal 152 to be controlled by relay switch 82, which is in turn controlled by the timer and control circuitry 84 via driving amplifier 88 and relay coil 92.

Figures 9 and 10 are partial cross-sectional views showing means for securing a switching unit 28 in an aperture 105 of a wall panel 26. In Figure 9, securing screws 100 are screwed into the wall panel 26 through screw hole recesses 102, in conventional manner. Two securing screws 100 and recesses 102 are provided to secure switching a unit 28 at opposed portions of the front rim 70. Figure 10 shows a screwless removable means for securing a switching unit 28 in an aperture 105 of wall panel 26. In this embodiment, each side of the rear casing 72 is provided with a pivot arm 108 attached to the rear of the casing 72 by means of a rcsiliently biased hinged portion 106. The pivot arm 108 projects from the rcsiliently biased hinged portion 106 at the rear of the casing 72 towards the from rim 70 at an acute angle to the side of the casing 72. The pivot arm 108 is also provided with an inwardly directed securing portion 110, which projects from the opposite end of the pivot arm 108 from the hinged portion 106, and into a projection aperture 126 in a front portion of the side face of casing 72. The front panel 36 of the switching unit 28 is provided with an access hole 112 in a position generally adjacent the end of the securing projection 110 which projects into the aperture 126. Additionally, the end of the securing projection 110 which is generally adjacent the access hole 112 is provided with a lever hole 122 large enough to accept the tip of a screwdriver or the like. The length of the pivot arm 108 is constructed such that the gap between a point on the forward face of securing projection 110 and the rear face of front rim 70 is marginally less than the thickness of a standard wall panel 26.

When the switching unit 28 is inserted in wall aperture 105 of the wall panel 26 the edges of the wall aperture 105 resiliently press pivot arm 108 towards the side of rear casing 72, thus pressing securing projection 110 into projection aperture 126. When the unit 28 has been pressed into the aperture to its full extent where the rear face of front rim 70 presses against wall panel 26, pivot arms 108 resiliently spring away from casing 72, pressing securing projections 110 against the rear of wall panel 26, and thus inhibiting removal of the unit 28 by wedging the wall panel 26 between securing projections 110 and front rim 70.

To remove the unit 28 from wall aperture 105 a screwdriver 114 is inserted into access hole 112 until the tip of screwdriver 114 engages lever hole 122 in the securing projection 110. The handle of the screwdriver 114 is then moved in lever direction 116 about a lever pivot point 124. This causes the screwdriver tip 120 to lever and pivot in a direction 118, resiliently drawing the securing projection 110 into projection aperture 126 and drawing pivot arm 108 towards the side face of rear casing 72. Performing this operation on both securing projections simultaneously draws both pivot arms 108 and securing projections 110 clear of the aperture 105 edges to allow removal of the switching unit 28.

Figures 11 and 12 show front perspective views of the portions of the switching unit 28 which arc exposed while the unit is installed in a wall panel 26. Both alternatives combine the front rim 70 with front cover plate 58 resulting in a one piece integrated front cover 59. In Figure 11, the unit 28 is secured to wall panel 26 by means of screws 142 in opposed side edges of front panel 36. The integrated front cover 59 is provided with hinges 56 in a manner similar to hinged front cover plate 58 in Figure 4. Along the top edge of front cover 59 arc provided two latch projections 140 each having an outwardly directed ridge 141 on the projecting end thereof. When the front cover 59 is moved to its closed position, latching projections 140 are received in latching apertures 143 provided adjacent the top edge of front panel 36. Inside the latching apertures 143 ridges 141 of the latching projections 140 cooperate and interengage with corresponding grooves within the latching apertures 143 to secure the front cover 59 in its closed position.

Figure 12 shows a modification of the arrangement shown in Figure 11, wherein the front cover 59 is completely detachable from front panel 36. In this arrangement latching projections 140 and latching apertures 143, as described above, are provided in place of the hinge portions 56 of Figure 11.

Whilst a variety of embodiments have been disclosed, it will be readily apparent to those skilled in the art that numerous other modifications and variations not mentioned above arc still possible without departing from the spirit and scope of the invention. For example, all of the embodiments described above include a front cover plate 58 or front cover 59 which, in use, allows a portion of switch 34 to extend therefrom whilst obscuring the remainder of the front panel 36. However, embodiments of the invention arc also envisaged where the front cover 59 and front panel 36 are formed integrally such that the features such as digital display 38, programming push buttons 40 and control push button 41 are located on the front cover 59, which is not removable or hingcably rotatablc from the remainder of the unit 28. Such an embodiment has the disadvantage that the switching unit, when installed, no longer appears as a standard wall mounted light switch, however, for some applications this feature may not be essential.

Claims

1. An electrical timer device (28) for installation in a building, comprising switching means (82) for, in use regulating the supply of electricity to electrical wiring of said building, and timer means (84) which in use controls said switching means to regulate said supply of electricity over a period of time.

2. An electrical timer device according to claim 1 , wherein the switching means regulates the supply of electricity by, in use, switching on or off the supply of electrical current to said wiring.

3. An electrical timer device according to claim 1 or 2, wherein the switching means includes terminals (150, 151, 152, 153) adapted for direct connection to wires (24, 25, 30, 31) of said electrical wiring.

4. An electrical timer device according to any preceding claim, wherein said timer means controls the switching means to switch the supply of electrical current on or off at predetermined times or intervals.

5. An electrical timer device according to claim 4, wherein said predetermined times or intervals can, in use, be programmed into said timer means.

6. An electrical timer device according to any preceding claim wherein said timer device is adapted for installation in a wall (26) of said building.

7. An electrical timer device according to claim 6, wherein when, in use, said timer device is installed in said wall, the device is supported within a hole (105) in a panel (26) of the wall, with a first portion of the device (72) extending into the wall, and a second portion (70) of the device projecting outwardly from the panel (26).

8. An electrical timer device according to claim 7 as appended to claim 3, wherein said terminals are located in or on said first portion of the device.

9. An electrical device according to any preceding claim including a control switch (47) which, in use, when in a first position enables said switching means to regulate said supply of electricity and, when in a second position prevents said switching means from regulating said supply of electricity.

10. An electrical device according to claim 9, including a manually operated switch (34) which, when said control switch is in said second position, is able to switch said supply of electricity on or off.

11. An electrical timer device according to any preceding claim, wherein said timer device is adapted for installation in a wall panel of said building, a portion of said device projecting outwardly from the panel including a front panel (58) through which projects a switching projection (34).

12. An electrical timer device according to claim 11, wherein said front panel (58) is hingedly connected to said outwardly projecting portion (70), to enable movement of said front panel between open and closed positions.

13. An electrical timer device according to claim 12, wherein when said front panel is in said open position programming controls (38, 40, 41) for programming said timer means are exposed.

14. An electrical timer device according to claim 11, wherein said front panel (59) is removably connected to said outwardly projecting portion.

15. An electrical timer device substantially as hereinbefore described with reference to the accompanying drawings.