GB2231954A

GB2231954A - A switch for automatically controlling electric appliances in a room

Info

Publication number: GB2231954A
Application number: GB8911472A
Authority: GB
Inventors: David Chen
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-05-18
Filing date: 1989-05-18
Publication date: 1990-11-28
Anticipated expiration: 2009-05-18
Also published as: GB8911472D0; GB2231954B

Abstract

The switch includes an infra-red sensor 1, a filter amplifier 2, a direction discrimination circuit 3 connected to output of the filter discrimination circuit for dividing into two signals according to the signal phase and a processor 4 connected to output of the direction discrimination circuit and having a comparating circuit 41 and a driving circuit 43 connected to output of the comparating circuit, whereby when the total number of persons entering into a room is more than the total number of persons leaving the room, a controller 6 circuit will be actuated to supply power to a load RL1, RL2, eg lights, and vice versa. <IMAGE>

Description

A SWITCH FOR AUTOMATICALLY CONTROLLING ELECTRIC APPLIACES IN A ROOM.

BACKGROUND OF THE INVENTION It is found that the conventional indoor automatic switch will turn on the electric lights when there is someone in the house but will turn off the lights when there is nobody indoor. The switch first utilizes infra-red ray to detect the infra-red ray emitted by the human body and then actuates a driving circuit to control the electric light. However, an infra-red sensor often cannot cove the everywhere in the house, i.e. every sensor has a dead point in detection. Although the problem can be solved by arranging more sensors, this will increase the cost. Furthermore, the detecting range may still be blocked by the furniture and the switch may have mistaken action.

It is, therefore, an object of the present invention to provide a switch which may obviate and mitigate the above-mentioned drawbacks.

SUMMARY OF THE INVENTION This invention relates to an intelligent switch for controlling the electric lights in a house or the like.

It is the primary object of the present invention to provide a switch which will turn on when the number of the persons entering into the house is greater than that leaving the house.

It is another object of the present invention to provide a switch which utilizes a processor to store and compare the number of persons entering into the house with the number of persons leaving the house so as to control the electric apparatus in the house automatically.

It is still another object of the present invention to provide a switch which is versatile in use.

It is a further object of the present invention to provide a switch which is simple in construction.

Other objects will become apparent when the following detailed description of the preferred embodiment is read in conjunction with the accompanying drawings wherein like numerals refer to like or similar parts.

BRIEF DESCRIPTION OF THE DRAWINGS FIG.1 is a block diagram of the present invention; and FIG.2 shows an electrical of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG.1, the present invention comprises an infra-red sensor 1 which is used to receive the infra-red ray emitted from the human body. The infra-red ray is then transmitted to a filter-amplifying circuit 2.

The output of the filter-amplifying circuit 2 is connected to a direction discrimination circuit 3 for detecting whether a person enters or leaves the house through the sensor 1. The sensor 1 is provided with a central partition so that the infra-red ray is divided into two beam, i.e. the left beam and the right beam. By means of the variation in the phase of the output signal of the filter-amplifying circuit 2, the direction discrimination circuit 3 is divided into two output signals representing the left and the right movement respectively, i.e. leaving the house or entering into the house. The output signals are then transmitted into a processor 4 which is constituted by a comparating circuit 41, a delaying circuit 42 and a driving circuit 43.The rally comparating circuit 41 may store the total number of person entering into the house and the total number of person leaving the house and then compare the two numbers. As the number of person entering into the house is greater than the number of person leaving the house, the rally comparating circuit 41 will send out a high potential which is appropriately delayed by the delaying circuit 42. Then the driving circuit 43 will push the right side controller 6 to connect power to the loads RL1 and RL2. If the load is an electric light the electric light will be turned on. As the number of person leaving the room is larger than the number of person entering into the room, the output of the comparating circuit 41 will be at low potential thereby cutting off the post circuits and therefore, automatically turning off the electric light.

The driving circuit 43 has two input signals. One is from a light shielding circuit 5 which will sense whether the outside light intensity is enough or not via a photo-sensitive resistor 51. When the outside light intensity is enough (at daytime), the shield driving circuit 43 cannot work. Only when the outside light intensity is insufficient will the driving circuit 43 be able to receive signal variation and change state. The other is from a keyboard circuit 7 which has an intensity key 71, a control key 72 and a sleep key 73. The intensity key 71 may control the driving circuit 43 to regulate the power of the load (the light intensity) so as to adapt to different needs of the users.

The control key 72 is used to manually turn on or turn off the the light. The sleep key 73 may, when pressed, gradually decrease the light intensity.

If the control key 72 and the sleep key 73 are both pressed downwards, the memory in the system will be reset so as to adapt to the practical need.

Referring to FIG. 2, the sensor 1 is disposed at the left side. By means of the filter amplifying circuit 2 constituted by two operational amplifier 21 and 22 and the resistor and capacitor feedback circuit, the sensed signal is appropriately filtered and amplified so as to be used with the post circuits. The direction discrimination circuit 3 is composed of two operational amplifier 31 and 32 coupled to the output of the filter amplifying circuit 2 and divided into left side movement and right side movement discriminating circuits. The output of the two operational amplifiers 31 and 32 are respectively connected to the inputs of the left movement SL and right movement SR of the processor 4 so as to detect the person entering into or leave the room. The processor 4 combines the three circuits 41, 42 and 43 shown in FIG 1 into an IC.Further, the processor 4 has two required to trigger the alternating current silicon controllers 61 and 62 and as the phase tranferring signals required to adjust the output power. In addition, the processor 4 has two selection terminals SEl and SE2 which are respectively connected to two switches 44 and 45 for selectively causing one or two outputs thereof to work.

Besides, the present invention may be conveniently mounted within a housing similar to that of a wall-type receptacle. In use, simply connect the two lines of the electric light with the present invention thereby facilitating the installation and enhancing the practicality.

Although this invention has been described with a certain degree of particularity, it is understood that the present disclosure is made by way of example only and that numerous changes in the construction and the combination and arrangement of parts may be resorted thereto without departing from the spirit and scope of the invention as hereinafter claimed, outputs OUT 1 and OUT 2 respectively connected to the gates of the two alternating current silicon controls 61 and 62 of the controller 6. The anodes 63 of the two alternating current silicon controls 61 and 62 are connected to the load. The CDS terminal of the processor 4 is connected to the light shielding circuit 5 which is constituted by an operational amplifier 52 with its input connected to a photo-sensitive resistor 51 via a variable resistor. The variable resistor is used to adjust the triggering sensitivity. The DIM, SLEEP and ON/OFF terminals of the processor 4 are connected to the keyboard circuits 7. The SYNC termianl is used to supply the AC mains to the processor through a sychronizing circuit 46 constituted by an operational amplifier 461 so as to use the sychronizing signal as the pulse

Claims

I CLAIM:

1. A switch comprising: a filter amplifier; a direction discrimination circuit connected to output of said filter amplifier for dividing into two signals according to the signal phase; and a processor connected to output of said direction discrimination circuit and having a rally comparating circuit and a driving circuit connected to output of the rally comparating circuit, said rally comparating circuit being able to compare total amount of person entering into a room with total amount of person leaving the room, said driving circuit being connected to a load.

whereby when the total amount of person entering into a room is more than the total amount of person leaving the room, the driving circuit will be actuated to supply power to the load and vice versa.

2. The switch as claimed in Claim 1, wherein said processor may be an integrated circuit and utilizes a light shielding circuit connected to input thereof to cut off the internal action, said light shielding circuit using a photo-sensitive resistor as outside intensity input signal and an operational amplifier to be a comparating circuit connected at the input with a variable resistor for adjusting the light triggering sensitivity.

3. The switch as claimed in Claim 1, further comprising a delaying circuit between the rally comparating circuit and said driving circuit.

4. The switch as claimed in Claim 1, further comprising a key-in circuit including a micro-switch for adjusting the power to the load, a manually operated control key and a sleep key for gradually decreasing the power to the load and the internal memory will be reset when any two of the keys are pressed simultaneously.

5. The switch as claimed in Claim 1, wherein said direction discrimination circuit has two operational amplifiers interconnected with said filter amplifier so as to sense signals of different phases, the output of said operational amplifiers being respectively connected with the two inputs of the rally comparating circuit of said processor.

6. The switch as claimed in Claim 1, wherein said sensor is divided into left and right portions so that the order of the sensed signal may indicate whether the person enters or leaves a room.