EP0775950A1

EP0775950A1 - Timer

Info

Publication number: EP0775950A1
Application number: EP96308480A
Authority: EP
Inventors: Assanumu Carlos Harada
Original assignee: Elsys Equipamentos de Segurancada Amazonia Ltda
Current assignee: Elsys Equipamentos de Segurancada Amazonia Ltda
Priority date: 1995-11-23
Filing date: 1996-11-22
Publication date: 1997-05-28
Also published as: BR9504997A

Abstract

The present invention refers to a timer for the control of equipment with electrical drivers in which is combined an electromechanical device and an electronic circuit.

The timer includes an electromechanical device (1) in conjunction with an electronic circuit (2), the electromechanical device (1) consisting of a surface (9) on which is printed, in encoded form, the states in which the equipment may be and a sensor (8) or a set of sensors (8) which move in relation to the surface (9) by means of an electromechanical transducer (3), detecting the printed codes, the electronic circuit (2) receiving signals from reading sensors (8) of the state codes, transducer signals (3) which exist in the equipment and command the electrical drivers (4), as well as the movement of the reading sensors (8) of the electromechanical device (1).

Description

The present invention relates to a timer for the control of equipment containing drivers for electrical loads and combines electromechanical and electronic components.
The same functions at present are carried out by known electromechanical timers or electronic timers. An embodiment of the present invention combines the advantages of both of these types in one device.
Typical electromechanical timers work with a rotating barrel moved by electrical motors and which have indentations whose position constitutes the different states of the equipment. The indentations open and close electrical contacts which directly switch on and off the equipment loads.
In an embodiment of the present invention, electrical sensors move in relation to a coded surface. In contrast, with the electromechanical timers, these sensors are used merely to read the state of the equipment while the switching of the electrical loads is accomplished through the use of electronic circuitry thus conferring greater reliability, performance and durability.
In particular, the sensors may be electrical contacts which move over a printed circuit board, where the tracks constitute an encoding of the states. In this embodiment, another advantage over the electromechanical timers is the fact that the encoding of the states of the printed circuit board can easily be altered in contrast to the indentations of the rotating barrels which are normally injection molded in plastic and cannot easily be changed.
In general, electronic timers need additional electronic displays to show the state of operation. This increases the price of the product. In an embodiment of the present invention, display of the state of operation is simpler, consisting of an indicator disc which rotates together with a cogwheel. Moreover, when the sensors are electrical contacts moving over a printed circuit board, the alteration of the codes is simple compared to the need to change the mask in the manufacture of the microcontroller as is necessary in the case of electronic timers.
An embodiment of the present invention seeks to remedy disadvantages of current technology by means of a timer which includes the following components:
an electromechanical device which contains the coding of the equipment states, functions as a visual indicator of the current state and has the additional advantage that it also allows the user to alter its state. Each state of the equipment corresponds to an action or set of actions which the equipment drivers must carry out. This electromechanical device is made up of a surface on which are printed, in encoded form, the various states of the equipment and a sensor or set of sensors which move in relation to this surface thus detecting the printed codes. The surface is divided into sectors, each one containing a specific code. The sensors may be of different types, for example, electrical contacts, photoelectric or magnetic or any other types, depending on the way the codes are printed on the surface. From here on, these sensors will be denominated as reading sensors. The movement of the reading sensors in relation to the encoded surface is obtained by the action of an electromechanical transducer such as, for example, a solenoid or step motor. This movement is made in steps, that is, the reading sensors are positioned over a sector of the encoded surface and remain there for an amount of time that is defined by the code itself, and in specific cases, by a combination of the codes with signals originated from existing transducers in the equipment. When this time has expired, the sensors move one step to the next sector of the encoded surface driven by the electronic circuit. In certain cases, the combination of the actual code with transducer signals may cause the reading sensors to jump to another sector ignoring the intermediate sectors.
An electronic circuit which receives the signals from the reading sensors and from possible equipment transducers, commands the electric loads in the equipment as well as the reading sensors of the electromechanical device.
The rate of angular dislocation can be programmed, through the electronic circuit, to be a function of the present state code detected by the reading sensors. This rate can be arbitrarily set and is an improvement over the standard electromechanical timer, whose angular rate depends on a synchronous motor, which advances the timer at fixed angular steps.
Any state can be decoded to represent an arbitrary sequence of electrical loads commands (on/off) and corresponding duration time, as opposed to typical electromechanical timers in which each state corresponds to a single set of load commands (on/off). This characteristic makes this novel approach more flexible, allowing complex sequences of loads commands to be easily designed. In this case, the sequences and corresponding timing will reside in the electronic circuit, typically a microcontroller, which will read the printed code through the reading sensors and will execute the proper programmed sequences of load commands.
The invention will now be described with reference to the attached diagrams in which:

Figure 1 illustrates a block diagram of a timer embodying the invention;
Figure 2 is a drawing of the timer of Figure 1; and
Figure 3 shows an example of copper tracks on the printed circuit board of a timer.

According to Figure 1, an electromechanical device (1) containing the encoding of the equipment states, is read by the electronic circuit (2) which also receives signals from transducers (3) contained within the equipment and, in accordance with the current state and the transducer signals (3), drives the electrical loads (4) and the electromechanical device (I).
In the diagram in Figure 2, a solenoid (5), when energized, drives a cogwheel (6) made of insulating material by means of mechanical arms (7a, 7b) which rotates in a given angle. Fixed to the cogwheel, are a number of electrical contacts (8) made of conductive material, such as brass, for example. These electrical contacts (8) move across a printed circuit board where a set of copper tracks (10) represents the digital codes of the various states of the equipment. This combination makes up the electromechanical device (1). The electronic circuit (2) can be mounted over the printed circuit board (9) as well as over a separate board.
As shown in Figure 3, the tracks (10) are arranged in circular form to be able to follow the trajectory of the contacts (8) when these move with the cogwheel (6). In this example, the contacts (8) are electrically interconnected and the inner track (10a) has no gaps and is electrically connected to the ground of the electronic circuit (2). In this way, a contact (8) touching another track (10) is grounded. The tracks which contain the code (10b, 10c, 10d, 10e) have a geometric form as shown in Figure 3; in the angular positions where it is desirable to ground a specific encoded track (10b, 10c, 10d, 10e), it is positioned in the trajectory of one of the contacts (8) and in the position in which grounding is undesirable it deviates from the trajectory of the contacts (8). In order to present a well-defined electrical voltage different from zero in the not grounded positions, each encoded track is connected to a resistor lead (11), whose other lead is connected to a voltage which is different from the ground. Thus, the codes reading by the electronic circuit is done by the detection of the encoded track's voltage. This is accomplished by the electronic circuit which detects the resistor voltages and then sends appropriate switching and driving signals to the electrical loads it is controlling.
Obviously, several modifications can be made in the present invention in the light of the above mentioned. Thus, it must be understood that, within the scope of these claims, the invention may be used differently from how it is specifically described.

Claims

A timer, for the control of equipment with electric loads characterized by an electromechanical device (1) in conjunction with an electronic circuit (2), the electromechanical device (1) being made up of a surface (9) in which is printed, in a digitally encoded form, the states in which the equipment may operate and at least one sensor (8), which moves in relation to the coded surface (9), by the action of an electromechanical transducer (5) to detect the printed codes and an electronic circuit (2) which receives the signals from the reading sensors (8) according to the state codes and transducer signals (5) which exist in the equipment and which can command the electrical loads as well as the forwarding of the reading sensors (8) of the electromechanical device (1).
A timer in accordance with claim 1, characterized by the fact that the surface (9) consists of a printed circuit board with tracks which (10a, 10b, 10c, 10d, 10e) represents the encoding of the states in which the equipment may be, and by the forwarding of the electrical contacts (8) in relation to the tracks resulting from the action of a solenoid or step motor (5) which dislocates a cogwheel (6) to which the contacts (8) are fixed, the electronic circuit detecting the track's electrical voltage (10a, 10b, 10c, 10d, 10e), of the printed circuit which are functions of the angular position of the electrical contacts (8) and which correspond to the states of the equipment, receiving transducer signals (3) and commanding the electrical loads (4) as well as the forwarding of the electrical contacts (8)of the electromechanical device (1).
A timer for the control of equipment with electrical loads characterised by an electromechanical device (1) and an electronic circuit (2), the electromechanical device (1) comprising at least one digitally encoded surface representing the states in which the equipment is to operate, and at least one sensor (8) which moves in relation to the encoded surface (9) to detect the coding, the electronic circuit (2) receiving signals in dependence on the detection of the encoded surface by the sensor (8) and being responsive thereto to control the electric loads.