WO2003076856A2

WO2003076856A2 - Electronic control for refrigerator

Info

Publication number: WO2003076856A2
Application number: PCT/BR2003/000032
Authority: WO
Inventors: Rui ASSUMPçÁO
Original assignee: Quantum Ind E Com De Equip Eletrônicos Ltda
Priority date: 2002-03-08
Filing date: 2003-03-07
Publication date: 2003-09-18
Also published as: BR8200405U; WO2003076856A3

Abstract

Electronic controller for refrigerator, being preprogrammed, with definition of 'Working temperature', hysteresis', the 'compressor(s) protection time', among other parameters, so that the controller receives signal(s) from the installed sensor(s) in order to measure the internal refrigerator temperature, the evaporator and the external temperatures, and with this measurement controls the operation of the refrigerator's compressor(s) in order to maintain the desired internal temperature, being comprised of: Controller/Display Module (6); Power Module (1); Cable (2) for Connection of the Power Module to the Controller/Display Module; temperature Sensor(s) (4) with cable (5) and connector.

Description

"ELECTRONIC CONTROL FOR REFRIGERATOR" The present model of utility relates to a specific control for series- manufactured refrigerators and freezers, which is pre-programmed, not requiring programming during installation thereof in the refrigerator. The controller receives signals from sensors installed in the refrigerator, measuring the refrigerator's internal temperature; it being possible further to measure the evaporator's temperature and the external temperature, and with these measurements to control the operation of the compressor(s), the defrosting resistance, or the refrigerator's ventilator, thereby maintaining the desired temperatures.

This equipment is comprised of the following components: Controller Module / Display; Power Module; Cable for Connection of the Power Module to the Controller/Display Module; temperature Sensor(s) with cable and connector. In the parametering for pre-programming, a "working temperature" is defined, being the average or minimum temperature of the circulating air one wants to maintain within the refrigerator. "Hysteresis", an upward or downward working temperature change is also defined, whereby the compressor(s) is(are) actuated of shutdown. Another datum related to the compressor(s) is the "compressor(s) protection time", which is counted since the moment the compressor(s) is(are) shutdown and determines how many seconds should lapse before they are actuated again. This is usually the gas pressure equalization time upstream and downstream of the capillary tube, in order to facilitate the compressor(s) start. In refrigerators employing a second compressor, the controller electronically retards the startup in relation to the first compressor, in order to prevent also the current surges in the mains. The evaporator defrosting resistance can be time- and also temperature - controlled, in the event that a sensor is provided on the evaporator. This time is counted from the moment when the refrigerator is connected to the mains. The frequency between defrosting cycles and the maximum duration thereof are characteristics defined at the product's development stage, as well as the maximum evaporator temperature for the end of the defrostmg. The controller has no clock maintenance battery. This means that, if electric power blackouts occur, the time counting for the next defrosting cycle starts again when the power is returned.

The temperature shown on the display can be subjected to several treatments, such as: - showing a temperature higher or lower than the measured temperature, at all times or only for a part of time.

- always showing the working temperature, provided that the measured temperature is within the hysteresis range, and quickly returning to display the measured temperature, should it leave this range. - setting on the display the measured temperature existing at the start of defrosting and continue to display it until the end of the defrosting. When the temperature falls again and becomes equal to the one set on the display, it returns to display the temperatures in a normal manner.

There is a possibility of using up to 3 different treatments, and the selection of the desired option will be done by means of jumpers.

It is possible to install a two- or three-position switch, to change the refrigerator's working temperature. This switch uses one or two inputs for jumpers.

There is an option of up to 64 different parameter combinations that also employs one of the three jumper inputs. This option is normally employed during the characteristics definition stage with the client.

The internal ventilator remains actuated all the time, except when the defrosting resistance is actuated, that is, there is no separate control for the ventilator and the resistance; when one is on, the other is off. One can also use one of the compressor outputs to provide independent actuation of the internal ventilator.

The controller has a technical resource employed for testing and adjustment during the manufacture thereof. This technical resource can be a button installed directly in the controller/display module or through a remote control actuator. After the controller is installed in the refrigerator, this technical resource can be used to test the refrigerator's operation. In refrigerators and freezers having an evaporator defrosting system, this technical resource can be used to actuate the defrosting. Accordingly, it is possible to test the entire defrosting system, without having to wait for the defrosting cycle times.

Special emergency functions can also be implemented. In refrigerators using defrosting resistance with a sensor installed in the evaporator, in the event of some kind of malfunction, one can make the other, internal temperature sensor to control the defrosting completion also. To that effect, a maximum internal temperature is specified to allow the defrosting. With this implementation, both sensors control the completion of defrosting. The other emergency function is that of total disabling of the controller and its outputs (except the ventilator), if the internal temperature falls below a specified limit.

The display shows the positive or negative refrigerator's working temperatures. Where it is negative, the signal will be shown through rectangular LEDs.

The compressor operation is indicated when the round LED is blinking intermittently and when the defrostmg resistance is on this LED is constantly on. When this LED is off, there is no active function in the compressor or in the defrosting resistance. Alert codes on operation problems can be defined in the programming and shown on the display, either intermittently or otherwise, as in the following examples: -99 - Internal temperature sensor disconnected or with problem.

- 00 - Evaporator temperature sensor disconnected or with problem.

The drawings accompanying and being an integral part of the present application best shown the composition and operation of the equipment now proposed.

Figure 1 is a perspective view of the power module (1), with the respective power and controller/display module connectors (2) and the input for connection of the sensor(s) or jumper(s) (3).

Figure 2 is a perspective view of the sensor (4) and the respective cable for connection (5) to the controller/display module.

Figure 3 is a perspective view of the controller/display module (6) presenting the digits and LED for indication of the compressor or defrosting actuation, comprised of a plastic material case (7) with a frame (8) and support for attachment to the refrigerator. The controller/display module possesses an electronic board storing the data programmed accordmg to the established parameters and controlling all defined functions.

Figure 4 is an exploded view of the display module, showing the component parts thereof: box (7) and support (9), the display (6) attached to the electronic board (10) with acrylic protection (11) and attached with the frame (8).

Figure 5 is a perspective view of the display module box (7), showing the position of the flexible and movable support (9) for attachment to the refrigerator, comprising a steel spring of a special format to support it in its installed position. Figure 6 in turn shows an example of the arrangement of the display module (7) near the refrigerator (10).

Accordingly, in a practical and efficient manner, an extremely useful product has been conceived, with accuracy in the temperature and time measurements, possessing a high cost-to-benefit ratio and also, since it is pre- programmed, designed and parametered pursuant to the client's specifications, being perfectly appropriate for the functions to which it is intended, without incorporating unnecessary costs in non-employed functions and elements. It is also possible to provide the equipment with specific programs, special functions and fixed or variable parameters, making it adaptable to various functions and applications.

Claims

CLAIMS l.ELECTRONIC CONTROLLER FOR REFRIGERATOR, characterized in that it performs the internal temperature control functions in refrigerators, with programming pre-established pursuant to the desired specifications;

2.ELECTRONIC CONTROLLER FOR REFRIGERATOR, characterized in that it is comprised of a controller with a thermostat (1), a sensor (3) and a display (6);

3.ELECTRONIC CONTROLLER FOR REFRIGERATOR, characterized in that it is provided, pursuant to claim 2, with an electronic controller (1) with the respective connectors (2) and connection input for sensor (3). The controller possesses a thermostat connected to the sensor, and the electronic board storing the programmed data;

4. ELECTRONIC CONTROLLER FOR REFRIGERATOR, characterized in that it is provided, pursuant to claim 2, with a sensor (4) and respective cable (5) for connection to the controller.

5. ELECTRONIC CONTROLLER FOR REFRIGERATOR, characterized in that it is provided, pursuant to claim 2, with a display (2) presenting the digits and LED for indication of operation, comprised of a plastic material box (7) with a frame (8) and support (9) for attachment to the refrigerator.