GB2492637A

GB2492637A - Manually enabled electrical timeswitch

Info

Publication number: GB2492637A
Application number: GB201211329A
Authority: GB
Inventors: Nicola Caroline Ternan Harris
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-07-08
Filing date: 2012-06-25
Publication date: 2013-01-09
Also published as: GB201211329D0; GB201111766D0; GB2492603A

Abstract

A time switch device controls the supply of electrical power to connected equipment by defining permissible time periods for potential activity within a cycle of adjustable length in cycles that may recur daily, weekly, monthly or annually but does not provide supply to the equipment automatically. The device comprises timer operated circuitry, power components and manual switches 9,10 controlling actual equipment activity. The housing of the device 1 can be a conventional electrical power connector and the power input can be directly wired. The device can be incorporated into the controlled equipment. The controlled equipment can be hard-wired to it or connected via an electrical socket. Programming functions of the timer can be accessible using a mechanical, magnetic or wireless key or by entering a code. The end of a period of activity can be signalled by adjustable audible or visible means. The device turns off the power to the equipment at the end of the timed period of activity but requires an additional manual control to enable power to be supplied.

Description

IMPROVED ELECTRICAL TIMES WITCH

Field of the Invention

The present invention relates to improved time controlled electrical switching

Background to the invention

Many electrical devices, in both domestic and commercial situations, can be controlled by external timeswitches to define the time periods when they are, or may be, active. These switches are of varying complexity but all operate by enabling the electrical power supply to connected equipment for preset time periods defined during a recurring 24 hour or weeldy cycle. During these periods the connected equipment is either activated automatically or is capable of being activated manually: a lamp connected to such a switch, for example, will activate automatically if it is either unswitched or left switched on, or it may be manually controlled if fitted with its own switch.

In certain circumstances a greater degree of control is desirable and the standard type of switch has some disadvantages: the equipment will be enabled in the same state as it was left when the previous period ended, which may not be desirable, and in some circumstances the time period settings may be overridden by an unauthorised user.

The aim of this invention is to provide a timeswitch which disconnects the power supply to connected equipment at the end of an active period, but does not restore it at the beginning of the next scheduled period unless a deliberate action is taken. There is considerable potential environmental benefit from the reduction in power consumption if equipment is not left powered up unless actually in use, and most equipment can safely be controlled by a timeswitch. Equipment controlled by this invention in a school or office, for example, Would automatically be switched off at a predetermined time and would not operate pointlessly at weekends or during holidays unless deliberately activated. In a domestic environment the invention could be used to ensure compliance with a lights out' time by a child absorbed in a book but would not cause the light to turn on again the following day until it is needed and deliberately activated.

The invention therefore offers additional environmental benefits compared to a normal timeswitch.

Summary of the invention

According to the present invention the solution lies in a device which permits activation of the connected equipment during the preset periods but does not itself cause such activation. Preferably the device requires a key or acces code to amend the preset times, and preferably it is hard-wired to the equipment so that its operation may not be evaded by moving the power connection to an uncontrolled outlet.

The device comprises timer circuitry and power switching components to which the controlled equipment can be connected preferably via wiring terminals. Preferably the timer is of an electronic type operating on one or more programmed cycles of adjustable length, including but not limited to; daily, weekly. monthly and annual cycles. The programmed cycles may be both factory pre-set and also user configured and access to its controls is restricted by a requirement for the use of an access code or a mechanical or wireless key including but not limited to; magnetic, WIN, bluetooth, RFID and infrared technology.

When the output of the timer circuitry is active during the pm-selected time periods non-locking on' and off' switches mounted on the device allow the power output to the connected equipment to be enabled or disabled as required. At the end of the active period the power output returns to its disabled condition and remains in this condition until the on' switch is again used whilst the timer output is active during the next scheduled time period.

Description of the preferred embodiment

The invention will now be exemplified with reference to the accompanying drawings in which: figure 1 is a perspective partly exploded view of a timeswitch unit in accordance with the invention and Figure 2 is a possible circuit schematic of the unit.

The embodiment shown in figures 1 & 2 represents currently the best method known to the applicant of putting the invention into practice, but is not the only way in which this could be achieved. It is illustrated and will now be described by way of example only.

Figure 1 illustrates a device comprising a housing (I), of plastic construction, with protruding pins (2) of a size, shape, spacing, material and orientation suitable to function as a UK 13A plug to 8S1363. The power cord (3) of the controlled device enters the housing via an opening into an access chamber and is secured by an appropriate strain relief (4). The cord is terminated to terminals (5) and the access chamber protected and shielded by cover (6).

The control circuitry is housed within the main body of the housing (1). In the particular example (which uses a magnetic key and a reed switch) shown the display (7) and control switches (8) for the timer circuit (14) are mounted on the top face of the housing for easy access when programming. The operation of the control switches is inhibited by reed switch (11) which is located inside the housing (1) at a convenient point (marked on the particular example shown by a cross inside a circle). The reed switch (11) is closed by the application and holding in position of a smalL magnet at the matted point and programming of the timer can proceed. When the magnet is removed no amendments are possible until it is re-applied, so that unauthorised changes are prevented.

The timer is an electronic circuit comprising a digital 24hr clock capable of being programmed to produce an output voltage (ON) for the duration of one or a number of periods of time during the day. If during a period when the timer circuitry is ON the normally open on' switch (9) is pressed the timer output voltage is briefly connected to the coil of a relay (12) causing its contacts to close. The timer output voltage is also routed through the normally closed OFF' switch (10) to one of the two sets of relay contacts and thence, when the relay is activated, to the relay coil. Briefly closing the ON' switch (9) will therefore cause the relay to latch on, passing the mains electrical power via the second set of relay contacts to the output terminals (5) and thus to the controlled equipment. A brief press of the normally closed off" switch 10 will break the circuit connecting the timer output voltage to the relay coil, and the relay will de-activate, disconnecting the power to the controlled equipment. These operations may be performed as many times as required whilst the timer is in its ON state.

At the end of the designated ON period of the timer circuitry the relay coil will no longer be supplied with the required voltage to keep it activated and it will return to its rest' position, disconnecting the mains power supply to the controlled equipment.

The unit thus permits the controlled equipment to be used normally during the preset periods of time, but requires deliberate manual activation so that the equipment will not automatically function and use power unless actually required. Unlike conventional plug-in timeswitches this unit is hard-wired to the controlled equipment so that bypassing the timer by plugging in elsewhere is not possible, and wiauthorised re-programming is also prevented.

Optionally an audible or visual warning of the imminent end of an active period could be incorporated. An accessible fuse 13 is incorporated into the unit, as the housing serves also as a 13A plug to BS1363.

Claims

<claim-text>CLAIMSI. A device for controlling the supply of electrical power to connected equipment by definition of permissible time periods for potential activity preset to occur within a cycle of adjustable length, including but not limited to daily, weekly, monthly and annual cycles but not providing automatic supply to the equipment comprising timer circuitry, power components and associated manual switch(es) controlling actual activity.</claim-text> <claim-text>2. A device according to claim I in which the housing of the equipment flinctions as a conventional electrical power connector.</claim-text> <claim-text>3. A device according to claim 1 in which the device is equipped with a directly wired electrical power input.</claim-text> <claim-text>4. A device according to claim I in which the device is incorporated into the controlled equipment.</claim-text> <claim-text>5. A device according to claim 1,2 or 3 in which the controlled equipment is directly hard-wired to the device.</claim-text> <claim-text>6. A device according to claim 1, 2 or 3 in which the power output to the controlled equipment is connected via a conventional electrical socket.</claim-text> <claim-text>7. A device according to claim 1,2, 3 or 4 in which the programming functions of the timer circuitry are only accessible by entering a code to the timer.</claim-text> <claim-text>8. A device according to claim 1,2,3 or 4 in which the programming functions of the timer circuitry are only accessible by use of a mechanical, magnetic or wireless key.</claim-text> <claim-text>9. A device according to any preceding claim in which the imminent end of a period of potential activity is signalled by audible OT visual means.</claim-text> <claim-text>10. A device according to claim 9 in which the warning signal is adjustable in nature, timing or level.</claim-text> <claim-text>11. Apparatus substantially as described herein with reference to and as illustrated in the accompanying drawings.</claim-text>