Timer for refrigerator

FIELD: refrigerator automatics.

SUBSTANCE: timer has power source, time counter, heater, defrosting pickup, compressor, three-contact relay, two rectifiers, and first and second quenching members. The common lead of the time counter is connected with the movable contact of the three-contact electromagnetic relay. The defrosting pickup is connected between the inlet of the time counter and the second unmovable contact of the relay. The heater is connected between the input of the time counter and the first pole of the power source. The outputs of the second rectifier are connected with the movable contact of the relay and first movable contact of the relay through the second quenching member.

EFFECT: reduced power consumption and enhanced design.

1 dwg

 

The invention relates to the field of automation and can be used for occasional inclusions of Executive automation devices of alternating current, such as a refrigeration device.

Known timer (patent RF №2167463, etc. 03.04.2000 g)containing a power source, a timer, heater, sensor, defrost termination, compressor, three-prong relay, the movable contact of which is connected to the second pole of the power source, the counting input of the counter time through the heater is connected to the second stationary contact of the relay and through the sensor defrost termination is connected to the first pole of the power source, the total output of the time counter connected to the first stationary contact of the relay and through the compressor is connected to the first pole of the power source, and the output from the first output winding of the relay, the second output winding of the relay connected to the second pole of the power source via the included controlling circuit representing serially connected threshold element, the rectifier and the first ballast resistor, the input rectifier connected between the stationary switching contacts three electromagnetic relays via a second ballast resistor.

The resistors in the famous diagram of the timer are absorbing elements and intended to suppress excessive voltage source is and power. While the main function of the second ballast resistor - accumulation of energy at the output of the rectifier is sufficient to relay.

In the operation of the relay (switching its movable contact from position “a” to position “b”) parallel to the second ballast resistor connects the first ballast resistor whose main function is to provide in conjunction with a second ballast resistor hold the relay in srabotanno condition.

A disadvantage of the known circuit timer are significant energy losses of the rectifier associated with the fact that when the movable contact of the relay in the initial position “a” (before the relay), the first ballast resistor is connected in parallel to the rectifier, i.e. the first ballast resistor bypasses the rectifier. Through the first ballast resistor current leakage, power supply rectifier. The lower the resistance value of the first ballast resistor, the greater the leakage current flowing through this resistor.

With increasing resistance values of the first ballast resistor reduces the ability to hold a three-prong relay in srabotanno state (position “b” of the rolling contact of the relay). In position “b” of the rolling contact of the relay of the first and second ballast resistors in luchytsia in parallel, therefore, when significant resistance values of the first ballast resistor voltage at the rectifier output may not be sufficient to hold the relay.

Thus, the resistance value of the first ballast resistor depends on the resistance values of the second ballast resistor and the magnitude of current necessary to keep the relay. Choosing each of these circuit elements are dependent on each other and constrained to each other.

In addition, the timer can be used in a refrigerating device, an electric circuit for connecting the common output of the time counter to a stationary contact of the electromagnetic relay, for example, in the freezers “STINOL” - 106, 112.

Using known by patent No. 2167463 circuit timer in the refrigeration device of another type (electric scheme which provides for the connection of the common output of the time counter to the rolling contact of the relay, such as refrigerators "DAEWOO", model FR-3501, 3502, 3503, FR-3801, 3802, 3803) is impossible. Easy switching total output of the time counter on the movable contact of the electromagnetic relay will not provide the specified algorithm schema, because the timer when such connection will be considered as the compressor operation time and pause time after defrost regardless of the position of the contact sensor defrost voltage is e on the time counter will be served in both positions of the rolling contact of the relay).

The technical problem solved by the invention, is expanding Arsenal of technical means related to the timers of the refrigeration device, reduced electricity consumption by reducing its losses in the process timer, to increase the degree of universality of the timer.

The problem is solved in that the timer cooling devices, containing a power source, a timer, heater, sensor, defrost termination, compressor, two rectifier, the first and second restraining elements, three-prong relay, the movable contact of which is connected to the second pole of the power source, the counting input of the counter time through the heater is connected to the first pole of the power source and through the sensor defrost termination with the second stationary contact of the relay, the total output of the time counter is connected to a movable contact of the relay, the compressor is enabled between the first stationary contact of the relay and the first pole of the power source, the first inputs of both rectifiers are connected to the common output of the time counter, the second input of the first rectifier through the first absorbing element is connected with the second fixed contact of the relay, and the second input of the second rectifier through the second restraining element connected to the first stationary contact of the relay, the outputs of both rectifiers are connected with the output of the time counter through placentas is sory United the threshold element and the relay coil.

In the proposed scheme the timer, the total output of the time counter is connected to a rolling three-prong contact of the electromagnetic relay.

The efficiency of the timer is provided that the sensor defrost is enabled between the counting input of the time counter and the second stationary contact of the relay and the heater is positioned between the counter input of the time counter and the first pole of the power source. The inputs of the second rectifier is connected on one side to the rolling contact of the relay, and on the other hand via a second restraining element to the first stationary contact of the relay.

In this arrangement, the connection of these elements is provided by the work counter and timer in General, for a given algorithm.

When the supply voltage the movable contact of the relay is in the normally-closed state “and” switching contacts. The current flows from the second pole of the power source through the timer, the heater to the first pole of the power source. This heater does not work, since its internal resistance is considerably less than the internal resistance of the meter time. At the same time, the current from the second pole of the power source is supplied to the compressor and then to the first pole of the power source. The compressor operates, the counter counts the operating time of the compressor. After dialing the cold closed contact sensor defrost, talk on inet flow through the circuit from the second pole of the power source through the first rectifier, the first restraining element, the sensor defrost heater to the first pole of the power source. If this heater is not working, because the relay contacts are in position “a”, which operates the compressor. When electric current flows through the first absorbing element begins the process of transition of the output voltage of the first rectifier. After reaching the voltage at the output of the first rectifier values sufficient for reliable operation of the relay opens the threshold element and provides the supply voltage to the second contact, winding of the relay. The relay and switch contacts in position “b” will occur upon the submission to the first coil winding relay the necessary voltages from the output of the timer corresponding to a time interval.

When the contact switch is in position “b”, because the contact sensor defrost closed, turns on the heater, the defrost refrigerator. When this current flows through the circuit from the second pole of the power source through the closed contacts of the sensor defrost heater to the first pole of the power source.

At the same time through the second absorbing element voltage is applied to the inputs of the second rectifier, the output of which sets the output voltage. In this case, the compressor is not running, and the current flows through the circuit: the second pole and the source of power, the second rectifier, the second restraining element, the compressor, the first pole of the power source. When the relay contacts in the position “b” circuit formed by the first rectifier and the first restraining element is short-circuited and does not work. The power winding of the relay is carried out only from the second rectifier, i.e. rectifiers operate alternately.

When the contacts in position “b” of the time counter stops working, because the input device is activated by the sensor defrost, the contacts of which are closed.

When defrosting has occurred, when the set temperature is reached, the contact sensor defrost is open. Through the time counter is the current through the circuit: the second pole of the power source, the timer, the heater, the first pole of the power source) and is counting pause after defrost, the compressor and the heater don't work, because the internal resistance of the meter time is significantly greater than the resistance of compressor and heater.

At the end of the pause time counter goes to its original state, the tension is removed from the first output winding of the relay and the relay contacts switch in position “a”, the cycle repeats.

Thus, operation of timer preset algorithm for those types of refrigerators, electric circuit which provides for the connection of the common you is Yes, the time counter to the rolling contact of the relay.

Since both rectifier operate alternately, the currents through both of the restraining element flow also alternately with a corresponding position of the rolling contact (“a” or “b”), causes no loss of energy at the input of each rectifier. The choice of the value of the basic characteristics of each of the restraining element is caused solely by the need to ensure operation of the relay and hold it in srabotanno condition. The choice is made for each of the restraining element independently regardless of the settings of the other of the restraining element. I.e. each rectifier and all other circuit elements of the timer is in optimum condition without unnecessary loss of energy.

As quenching can be selected such elements, which provide damping excessive voltage by its resistance (active or reactive). The value of the energy accumulated at the output of the rectifier, is inversely proportional to the magnitude of this resistance.

The magnitude of this resistance is the main characteristic of the absorbing element.

The choice of the value of the basic characteristics of the first absorbing element is determined only necessary response time three-prong relay. The choice of the value of the basic characteristics of the second restraining element is determined solely by the fact that when the ACOM its value will be holding relay in srabotanno condition. The choice of the values of the basic characteristics of both the quenching of the elements is determined only by the above conditions and does not depend on the value of the basic characteristics of the other of the restraining element, because when the timer both quenching element do not affect each other.

Thus, reduced energy losses during operation of the timer, and also ensures its versatility due to the fact that the choice of circuit elements (first and second restraining elements) is determined only by their functions and independent from one another, which allows for fewer restrictions to change some characteristics of the timer (for example, the time delay relay after issuing a signal meter or consumption of timer mode operation of the compressor depending on the conditions of its use.

The prior art is not revealed structures timers, characterized by the claimed combination of features, therefore, the present invention meets the patentability criteria of “novelty”.

The claimed combination of features of the invention, which provides a larger Arsenal of technical means related to the timers of the refrigeration device, reduced electricity consumption by reducing its losses in the process timer, to increase the degree of universality of the timer is compared with the known of the anti-shudder performance techniques, allows to make a conclusion that the claimed invention meets the patentability criterion of “inventive step”.

The drawing shows a block diagram of the timer.

The timer contains:

1. The time counter.

2. Three electromagnetic relays.

3. The threshold element.

4. The rectifier 1 power.

5. The rectifier 2 power.

6. Resistor 1.

7. The resistor 2.

8. Switching the three-prong contacts of the electromagnetic relay.

9, 10, 11. The elements of the periodic inclusion of the controlled device (9 - heater; 10 - sensor defrost termination; 11 - compressor).

12. The first pole of the power source.

13. The second pole of the power source.

The movable contact of the relay 2 is connected to the second pole of the power source 13. The counting input of counter 1 time through the heater 9 is connected to the first pole 12 of the power source and through the sensor 10 defrost termination connected to the second stationary contact of the relay. The total output of counter 1 time connected with a movable contact of the relay 2. The compressor 11 is included between the fixed contact “a” of the relay 2 and the first pole 12 to the power source. The output of counter 1 is connected to the first output winding of the relay 2. The first inputs of the rectifiers 4 and 5 are connected to the common output of counter 1. The second output of the rectifier 4 through the resistor 6 is connected to the fixed contact “b” relay2, and the second output of the rectifier 5 through the resistor 7 is connected with a fixed contact “a” relay 2.

The outputs of both rectifiers 4 and 5 across the threshold element 3 is connected to the second output winding of the relay 2.

The device operates as follows.

The timer included in the system defrost the refrigerator.

When the supply voltage is movable relay contact 2 is in the normally-closed state "and" switching contacts 8. Over the counter 1 is current and is the counting of the operation time of the compressor 11. When the heater 9 is not working, because the internal resistance of the meter 1 is significantly greater than the resistance of the heater 9. After a set of cold contact sensor 10 is closed, resulting in the resistor 6 voltage is applied to the inputs of the rectifier 4 and starts the transition process of establishing its output voltage. When you reach a voltage sufficient for reliable operation of the relay 2 opens the threshold element 3 and supplies the supply voltage to the second contact of the winding of an electromagnetic relay 2. The relay 2 and the switching contacts 8 in position “b” will occur upon the submission to the first winding of the relay coil 2 is required voltages from the output of the counter 1, the corresponding time interval.

When the switching contact 8 from position “a” to position “b” of the switch is raised by the heater 9 (closed contacts of the sensor 10), starts the defrosting of the refrigerator. At the same time through the resistor 7 voltage is applied to the inputs of the rectifier 5, the output of which sets the output voltage. When the contacts 8 in position “b” counter 1 stops working, because its input pins device is activated by the sensor 10, the contacts of which are closed.

When defrosting has occurred, when the set temperature is reached, the contacts of the sensor 10 is open. Over the counter 1 is current and is counting pause after defrost, the compressor 11 and the heater 9 do not work because of the internal resistance of the meter 1 is significantly greater than the resistance of the compressor 11 and the heater 9.

At the end of the pause counter 1 enters the initial state, the tension is removed from the first output winding of the relay 2, and the contacts 8 are switched to the position “a”, the cycle repeats.

The timer cooling devices, containing a power source, a timer, heater, sensor, defrost termination, compressor, two rectifier, the first and second restraining elements, three-prong relay, the movable contact of which is connected to the second pole of the power source, the counting input of the counter time through the heater is connected to the first pole of the power source and through the sensor defrost termination with the second stationary contact of the relay, the total output of the time counter connect the movable contact of the relay, the compressor is enabled between the first stationary contact of the relay and the first pole of the power source, the first inputs of both rectifiers are connected to the common output of the time counter, the second input of the first rectifier through the first absorbing element is connected with the second fixed contact of the relay, and the second input of the second rectifier through the second restraining element connected to the first stationary contact of the relay, the outputs of both rectifiers are connected with the output of the time counter connected in series through the threshold element and the relay coil.



 

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The invention relates to automation and can be used for periodic inclusions of Executive automation devices AC, in particular for systems defrosting the freezer

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1 dwg

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1 dwg

Timer // 2353996

FIELD: physics.

SUBSTANCE: timer comprises power supply source, time counter, heater, detector of defrosting completion, compressor, rectifier, quenching element, voltage limiter, three-pin electromagnet relay, movable contact of which is connected to the second pole of power supply source; common lead of time counter is connected to the first fixed relay contact and via compressor - to the first pole of power supply source; counter inlet of time counter via heater is connected to the second fixed relay contact and via detector of defrosting completion - to the first pole of power supply source; outlet of time counter is connected to the first lead of relay winding, the second lead of which via circuit of serially connected rectifier and quenching element is connected to the second fixed relay contact; common point of the second lead of relay winding and circuit formed by serially connected rectifier and quenching element is connected to common lead of time counter via voltage limiter.

EFFECT: increased reliability of operation.

1 dwg

Defrosting timer // 2353997

FIELD: physics.

SUBSTANCE: defrosting timer comprises power supply source, time counter, heater, detector of defrosting completion, compressor, voltage limiter, the first and second rectifiers, the first and second quenching elements, three-pin electromagnet relay, movable contact of which is connected to the second pole of power supply source; counter inlet of time counter via heater is connected to the first pole of power supply source, and via detector of defrosting completion - to the second fixed contact of relay; common output of time counter is connected to the second pole of power supply source; output of time counter is connected to the first output of relay winding, the second output of which via chain from serially joined first rectifier and first quenching element is connected to the second fixed contact of relay; common point of the second output of relay winding and chain of the first rectifier and the first quenching element is connected to the common output of time counter via voltage limiter and via chain of the second rectifier and second quenching element is connected with the first fixed contact of relay; the first fixed contact of relay via compressor is connected to the first pole of power supply source.

EFFECT: simplified design and increased reliability of operation.

1 dwg

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