CN110671768B

CN110671768B - Control system of cold accumulation central air conditioner

Info

Publication number: CN110671768B
Application number: CN201911013807.8A
Authority: CN
Inventors: 王俊; 李德英; 汪思维
Original assignee: Shenzhen Junan Environmental Technology Co ltd
Current assignee: Shenzhen Junan Environmental Technology Co ltd
Priority date: 2019-10-23
Filing date: 2019-10-23
Publication date: 2021-07-13
Anticipated expiration: 2039-10-23
Also published as: CN110671768A

Abstract

The invention relates to a control system of a cold accumulation central air conditioner, which relates to the technical field of refrigeration equipment and comprises a refrigeration host, a cooling tower, a main high-pressure pipe communicated with the refrigeration host, an output pipe communicated with the cooling tower and a protection device, wherein the protection device comprises a branch pipe communicated with the main high-pressure pipe, a standby pipe communicated with the main high-pressure pipe, a switching valve, a first hydraulic sensor arranged on the branch pipe and a control module, one ends of the branch pipe and the standby pipe are communicated with the output pipe, a blocking valve is arranged on the output pipe, when the hydraulic pressure detected by the first hydraulic sensor is lower than a set value, the control module controls the switching valve to close the channels of the main high-pressure pipe and the branch pipe and open the channels of the main high-pressure pipe and the standby pipe, and simultaneously the control module controls the valve to close the. The invention has the effect of reducing the loss of the refrigerant when the branch pipe is damaged and leaks so as to keep the normal operation of the air conditioning system.

Description

Control system of cold accumulation central air conditioner

Technical Field

The invention relates to the technical field of refrigeration equipment, in particular to a control system of a cold accumulation central air conditioner.

Background

At present, the refrigeration technology for air conditioner belongs to the common refrigeration range, and mainly adopts a liquid vaporization refrigeration method, namely, the principle that the specific latent heat is absorbed in the liquid vaporization process is utilized. And the liquid pressure is different, and its boiling point is also different, and the lower the pressure, the lower the boiling point. The refrigerant evaporates at low temperature and low pressure to produce a cold effect and condenses at normal temperature and high pressure to give off heat to the surrounding environment or the refrigerant.

The central air-conditioning system mainly comprises a refrigeration host, a cooling tower and a fan coil, wherein a pipeline between the refrigeration host and the cooling tower is a high-pressure section, and a pipeline between the refrigeration host and the fan coil is a low-pressure section pipeline. The refrigeration host is used for compressing the refrigerant so as to convert the refrigerant from a gaseous state to a liquid state, the cooling tower is used for cooling the compressed and heated refrigerant, and the fan coil is used for realizing heat exchange between the vaporized refrigerant and indoor air so as to achieve the cooling effect.

The above prior art solutions have the following drawbacks: the pipeline of the high-pressure section of the air-conditioning system is easy to damage after long-term use, so that the leakage of the refrigerant is caused, the total amount of the refrigerant circulating in the air-conditioning system is continuously reduced, the fault of the refrigeration system is caused, and the normal refrigeration is influenced.

Disclosure of Invention

The invention aims to provide a control system of a cold accumulation central air conditioner, which can reduce the loss of a refrigerant when a branch pipe is damaged and leaks, and keep the normal circulation of the refrigerant, thereby keeping the normal operation of the air conditioning system.

The above object of the present invention is achieved by the following technical solutions:

a control system of a cold accumulation central air conditioner comprises a refrigeration host, a cooling tower, a main high-pressure pipe communicated with the refrigeration host and used for transmitting high-pressure refrigerant, an output pipe communicated with the cooling tower and a protection device arranged between the main high-pressure pipe and the output pipe, wherein the protection device comprises a branch pipe communicated with the main high-pressure pipe, a standby pipe communicated with the main high-pressure pipe, a switching valve used for switching the flow direction of the refrigerant in the main high-pressure pipe to the branch pipe or the standby pipe, a first hydraulic pressure sensor arranged on the branch pipe and used for detecting the hydraulic pressure of the refrigerant in the branch pipe and a control module electrically connected with the first hydraulic pressure sensor and used for receiving electric signals, one end of each of the branch pipe and the standby pipe is communicated with the output pipe, a blocking valve used for switching the output pipe to be communicated with the branch pipe or the standby pipe is arranged on the output pipe, and the control module controls the switching valve to close, and meanwhile, the control module controls the blocking valve to close the channels of the branch pipe and the output pipe and open the channels of the standby pipe and the output pipe.

By adopting the technical scheme, the main high-pressure pipe, the branch pipe and the output pipe are used for transmitting the high-pressure refrigerant between the refrigeration main machine and the cooling tower, and when the branch pipe is damaged and the refrigerant leaks, the hydraulic pressure in the branch pipe can be reduced; at the moment, the hydraulic pressure detected by the first hydraulic pressure sensor is lower than a set value, so that the control module controls the switching valve to close the channel of the main high-pressure pipe and the branch pipe and open the channel of the main high-pressure pipe and the standby pipe, and simultaneously controls the blocking valve to close the channel of the branch pipe and the output pipe and open the channel of the standby pipe and the output pipe, so that the standby pipe is started to replace the branch pipe to realize the circulation of the refrigerant, and meanwhile, the phenomenon that the circulating refrigerant in the air conditioning system is continuously lost is avoided, and the normal operation of the air conditioning system is.

The invention is further configured to: the diverter valve all adopts the three-way valve with blocking the valve, and the import of diverter valve communicates in total high-pressure pipe and its export communicates respectively in branch pipe, stand-by pipe, the import of blocking the valve communicates in output tube and its export communicates respectively in branch pipe, stand-by pipe.

By adopting the technical scheme, the three-way valve is provided with the two inlets, one inlet is simultaneously communicated with only one outlet, and when the electromagnetic valve of the three-way valve acts, the outlet communicated with the inlet is switched to change the flow direction of the refrigerant, so that the effect that the refrigerant is switched to the flow direction standby pipe from the flow direction branch pipe is realized.

The invention is further configured to: the control module is electrically connected with an alarm, and when the hydraulic pressure detected by the first hydraulic pressure sensor is lower than a set value, the control module controls the alarm to send an alarm signal.

Through adopting above-mentioned technical scheme, when the branch pipe makes hydraulic pressure descend because of leaking, first hydraulic pressure sensor triggers so that control module control reports an emergency and asks for help or increased vigilance the piece and sends alarm signal to this suggestion operating personnel in time carries out troubleshooting, makes things convenient for in time salvageing of branch pipe.

The invention is further configured to: the control module comprises a detection assembly and a switch piece, the detection assembly comprises a first resistor, a second resistor and a first voltage comparator, the first resistor and the second resistor are connected in series in the same power supply loop, the connection point of the first resistor and the second resistor is connected to the + input end of the first voltage comparator, the output end of the first hydraulic sensor is connected with the-input end of the first voltage comparator, and when the hydraulic pressure of the first hydraulic sensor is lower than a set value, the output end of the first voltage comparator outputs a switch signal.

By adopting the technical scheme, the voltage comparator has the characteristic that when the voltage at the + input end is higher than the voltage at the-input end, a high-level signal is output, and when the refrigerant hydraulic pressure detected by the first hydraulic pressure sensor is reduced, the output voltage value is reduced, and when the potential at the-input end is reduced to be lower than the potential at the + input end, the first voltage comparator outputs the high-level signal, namely a switching signal.

The invention is further configured to: the switching element comprises a first NPN type triode, the base electrode of the first NPN type triode receives a switching signal, the emitting electrode of the first NPN type triode is grounded, the collector electrode of the first NPN type triode is connected with the coil of the electromagnetic valve S1 of the switching valve and the coil of the electromagnetic valve S2 of the blocking valve, and the coil of the electromagnetic valve S1 and the other end of the coil of the electromagnetic valve S2 are connected with a VCC end.

By adopting the technical scheme, the base electrode of the first NPN type triode is conducted due to the input of a high level signal, namely a switching signal, at the moment, the electromagnetic valve S1 and the electromagnetic valve S2 are simultaneously electrified to act, so that the switching valve is controlled to close the channel between the main high-voltage pipe and the branch pipe and open the channel between the main high-voltage pipe and the standby pipe, and the control module controls the blocking valve to close the channel between the branch pipe and the output pipe and open the channel between the standby pipe and the output pipe, so that the standby pipe is started to replace the branch pipe to realize the circulation of the refrigerant, and the normal operation of the air conditioning system is maintained.

The invention is further configured to: the control module further comprises a second hydraulic sensor used for detecting hydraulic pressure in the main high-pressure pipe and an electric control valve arranged on the side, close to the refrigeration host, of the main high-pressure pipe, and when the hydraulic pressure measured by the second hydraulic sensor is lower than a set value, the control module controls the electric control valve to cut off a refrigerant output by the refrigeration host.

By adopting the technical scheme, when the branch pipe and the standby pipe leak simultaneously, the refrigerant in the main high-pressure pipe is lost, so that the hydraulic pressure detected by the second hydraulic pressure sensor is continuously reduced, and when the hydraulic pressure is lower than a set value, the control module controls the electric control valve to cut off the refrigerant output by the refrigeration host machine, so that the continuous loss of the refrigerant is reduced.

The invention is further configured to: the warning piece comprises a third NPN triode, a relay and a warning lamp, wherein the base electrode of the third NPN triode receives a switching signal, the emitting electrode of the third NPN triode is grounded, the collector electrode of the third NPN triode is connected to one end of a relay coil, the other end of the relay coil is connected with a VCC end, a normally open contact of the relay coil is connected between the VCC end and the warning lamp in series, and one end of the warning lamp is grounded.

By adopting the technical scheme, when the base of the third NPN type triode receives a high level signal, namely a switching signal, the third NPN type triode is conducted to enable the coil of the relay to be electrified and send out an excitation signal, and the normally open contact of the relay is closed at the moment to enable the warning lamp to be lightened due to the electrification, so that an alarm signal is sent out to prompt an operator to maintain the branch pipe in time.

The invention is further configured to: the alarm piece further comprises an oscillator, a normally open contact of the relay coil is connected between the VCC end and the input end of the oscillator in series, and the other end of the alarm lamp is connected to the output end of the oscillator.

By adopting the technical scheme, when the base of the third NPN type triode receives the switch signal, the normally open contact of the relay is closed, the oscillator is electrified at the moment and outputs the oscillation signal, so that the warning lamp is electrified intermittently to generate a flickering phenomenon, and the warning effect is improved.

The invention is further configured to: the branch pipe is communicated with an injection pipe, the injection pipe is detachably connected with an injection pipe, the injection pipe is communicated with a sealed tank containing high-pressure refrigerant, and the injection pipe is provided with a control valve.

By adopting the technical scheme, when the injection pipe is connected with the injection pipe, the sealing tank is communicated with the injection pipe, and when the control valve is opened, the high-pressure refrigerant in the sealing tank enters the newly-connected branch pipe along the injection pipe and the injection pipe, so that the newly-connected branch pipe is filled with the refrigerant, and the hydraulic pressure of the refrigerant is raised back to the hydraulic level of the total high-pressure pipe, thereby avoiding the phenomenon that the high-pressure refrigerant is vaporized due to the rapid reduction of the hydraulic pressure when the switching valve is switched to the branch pipe, further avoiding the influence on the normal circulation of the refrigerant, simultaneously compensating the total amount of the refrigerant circulating in the air conditioning system, and reducing the influence of the lost refrigerant on the refrigeration effect.

The invention is further configured to: the opening part of injection pipe is provided with the spacing ring, the internal diameter of spacing ring is less than the internal diameter of injection pipe, it is provided with the embolism to slide in the injection pipe, run through with the spacing ring butt side on the embolism and seted up the water conservancy diversion hole, injection pipe one end is provided with triggers the bolt, trigger and set up the through-hole of intercommunication sealed can on the bolt, trigger bolt and spacing ring grafting cooperation and promote the embolism when triggering the bolt and insert in the spacing ring and remove so that water conservancy diversion hole and through-hole intercommunication.

By adopting the technical scheme, when the trigger bolt of the refrigerant injection pipe is inserted into the limiting ring, the plug is pushed to move so as to communicate the flow guide hole with the through hole, so that the injection pipe and the refrigerant injection pipe are connected and communicated with the sealing tank and the branch pipe, the refrigerant is conveniently filled, and after the refrigerant is filled, the plug is tightly pressed against the limiting ring under the hydraulic action so as to close the flow guide hole opposite to the limiting ring on the plug, so that the refrigerant is prevented from leaking.

In conclusion, the beneficial technical effects of the invention are as follows:

when the branch pipe has the condition of refrigerant leakage, the hydraulic pressure in the branch pipe is reduced; at the moment, the hydraulic pressure detected by the first hydraulic pressure sensor is lower than a set value, so that the control module controls the switching valve and the blocking valve, starts the standby pipe to replace the branch pipe to realize the circulation of the refrigerant, and simultaneously avoids the phenomenon that the circulating refrigerant in the air conditioning system is continuously lost, thereby keeping the normal operation of the air conditioning system;

when the hydraulic pressure of the branch pipe is reduced due to leakage, the first hydraulic sensor is triggered to enable the control module to control the alarm piece to send an alarm signal, so that an operator is prompted to carry out fault removal in time, and the branch pipe is convenient to repair in time;

when the control valve is opened, the high-pressure refrigerant in the sealing tank enters the newly connected branch pipe along the refrigerant injection pipe and the injection pipe, so that the newly connected branch pipe is filled with the refrigerant, the hydraulic pressure of the refrigerant is raised back to the hydraulic level of the total high-pressure pipe, the phenomenon that the high-pressure refrigerant is vaporized due to the rapid reduction of the hydraulic pressure when the switching valve is switched to the branch pipe is avoided, the normal circulation of the refrigerant is prevented from being influenced, meanwhile, the total amount of the refrigerant circulating in the air conditioning system is compensated, and the influence of the lost refrigerant on the refrigeration effect is reduced.

Drawings

FIG. 1 is a schematic view of the overall structure of the present embodiment;

FIG. 2 is a functional block diagram of the present embodiment;

FIG. 3 is a schematic circuit diagram of the present embodiment;

FIG. 4 is a partial schematic structural view of the present embodiment, mainly showing the injection pipe;

fig. 5 is a schematic diagram of a partial explosion structure of the present embodiment, mainly showing a plug.

Reference numerals: 1. a refrigeration host; 11. a cooling tower; 12. a total high pressure pipe; 13. an output pipe; 2. a protection device; 21. a branch pipe; 22. a standby pipe; 23. a first hydraulic pressure sensor; 24. a control module; 241. a detection component; 242. a switch member; 243. an alarm; 244. a second hydraulic pressure sensor; 3. an injection pipe; 31. a limiting ring; 32. plugging; 4. an agent injection pipe; 41. triggering the bolt; 42. a through hole; 43. sealing the tank; 44. and (4) controlling the valve.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, the control system for a cold storage central air conditioner disclosed by the invention comprises a refrigeration host 1, a cooling tower 11, a total high-pressure pipe 12, an output pipe 13 communicated with the cooling tower 11, and a protection device 2 arranged between the total high-pressure pipe 12 and the output pipe 13. The refrigeration main machine 1 is used for outputting high-pressure refrigerant, and the total high-pressure pipe 12 is communicated with the refrigeration main machine 1 so as to transmit the high-pressure refrigerant. The cooling tower 11 is used to cool the compressed high-pressure refrigerant to reduce the heat of the refrigerant.

The protection device 2 includes a branch pipe 21 communicating with the total high-pressure pipe 12, a reserve pipe 22 communicating with the total high-pressure pipe 12, a switching valve for switching a flow direction of the refrigerant in the total high-pressure pipe 12 to the branch pipe 21 or the reserve pipe 22, a first hydraulic pressure sensor 23 provided on the branch pipe 21 to detect a hydraulic pressure of the refrigerant in the branch pipe 21, and a control module 24 electrically connected to the first hydraulic pressure sensor 23 to receive an electrical signal. The branch pipe 21 and the spare pipe 22 are parallel to each other, the specifications of the branch pipe 21 and the spare pipe 22 are consistent and the inner diameters of the main high-pressure pipe 12 and the spare pipe are consistent, one ends of the branch pipe 21 and the spare pipe 22 are communicated with the output pipe 13, and the high-pressure refrigerant flows to the cooling tower 11 along the main high-pressure pipe 12, the branch pipe 21 and the output pipe 13 or flows to the cooling tower 11 along the main high-pressure pipe 12, the spare pipe 22 and the output pipe 13.

And the output pipe 13 is provided with a blocking valve for switching the output pipe 13 to be communicated with the branch pipe 21 or the spare pipe 22, the switching valve and the blocking valve adopt three-way valves, the three-way valves are provided with an inlet and two outlets, and one inlet is simultaneously communicated with only one of the outlets. The inlet of the switching valve is connected to the total high pressure pipe 12 and the outlet thereof is connected to the branch pipe 21 and the reserve pipe 22, respectively, and the inlet of the blocking valve is connected to the output pipe 13 and the outlet thereof is connected to the branch pipe 21 and the reserve pipe 22, respectively. When the solenoid valve of the three-way valve is actuated, the outlet communicated with the inlet is switched to change the flow direction of the refrigerant, thereby achieving the effect of switching the refrigerant from the flow direction branch pipe 21 to the flow direction standby pipe 22.

When the hydraulic pressure detected by the first hydraulic pressure sensor 23 is lower than a set value, the control module 24 controls the switching valve to close the passage between the main high-pressure pipe 12 and the branch pipe 21 and open the passage between the main high-pressure pipe 12 and the backup pipe 22. Meanwhile, the control module 24 controls the blocking valve to close the channels of the branch pipe 21 and the output pipe 13 and open the channels of the standby pipe 22 and the output pipe 13, so that the standby pipe 22 is started to replace the branch pipe 21 to realize the circulation of the refrigerant, the normal circulation of the refrigerant is realized, and the phenomenon that the circulating refrigerant in the air conditioning system continuously runs off is avoided, thereby the normal operation of the air conditioning system is maintained. The backup pipe 22 is filled with a high-pressure refrigerant and has a hydraulic pressure identical to that of the main high-pressure pipe 12, thereby compensating for the refrigerant circulating in the air conditioning system.

Referring to fig. 2 and 3, the control module 24 includes a detection assembly 241 and a switch 242, wherein the detection assembly 241 includes a first resistor R1, a second resistor R2 and a first voltage comparator N1. The first resistor R1 and the second resistor R2 are connected in series in the same power supply loop to form a voltage divider circuit, and the connection point of the two is connected to the "+" input end of the first voltage comparator N1. The first hydraulic sensor 23 includes a pressure sensitive resistor RT and a first ground resistor R4, the pressure sensitive resistor RT and the first ground resistor R4 are connected in series to the same power supply circuit to form a voltage dividing circuit, the pressure sensitive resistor RT is connected to the VCC terminal, and a connection point of the pressure sensitive resistor RT and the first ground resistor R4 is connected to the "-" input terminal of the first voltage comparator N1. The output terminal of the first voltage comparator N1 outputs a switching signal when the hydraulic pressure of the first hydraulic pressure sensor 23 is lower than a set value.

The switching device 242 includes a first NPN transistor Q1, a base of the first NPN transistor Q1 receives the switching signal, an emitter thereof is grounded, a collector thereof is connected to the solenoid valve S1 coil of the switching valve and the solenoid valve S2 coil of the blocking valve, and the solenoid valve S1 coil and the solenoid valve S2 coil are connected to a VCC terminal.

The pressure sensitive resistor has a characteristic that the resistance value is larger as the pressure to be applied is smaller, and thus the potential of the connection point of the pressure sensitive resistor RT and the first ground resistor R4 is lowered as the hydraulic pressure in the branch pipe 21 is increased. The voltage signal inputted to the first voltage comparator N1 "+" from the connection point of the first resistor R1 and the second resistor R2 is at a set potential. And the voltage comparator has a characteristic of outputting a high level signal when the voltage at the "+" input terminal is higher than that at the "-" input terminal, so that the first voltage comparator N1 outputs a high level signal, i.e., a switching signal, when the potential of the connection point of the pressure sensitive resistor RT and the first ground resistor R4 is lowered to be lower than a set potential.

The base of the first NPN transistor Q1 turns on the first NPN transistor Q1 by inputting a high level signal, i.e., a switching signal, and at this time, the solenoid valve S1 and the solenoid valve S2 are simultaneously energized to operate, so as to control the switching valve to close the passages of the main high-pressure pipe 12 and the branch pipe 21 and open the passages of the main high-pressure pipe 12 and the standby pipe 22, and control the blocking valve to close the passages of the branch pipe 21 and the output pipe 13 and open the passages of the standby pipe 22 and the output pipe 13, so that the standby pipe 22 is started to replace the branch pipe 21 to realize the circulation of the refrigerant, thereby maintaining the normal operation of the air conditioning system.

The control module 24 further includes a second hydraulic pressure sensor 244 (see fig. 2) for detecting a hydraulic pressure in the total high-pressure pipe 12, an electric control valve disposed on the side of the total high-pressure pipe 12 close to the refrigeration main unit 1, a second voltage comparator N2, and a second NPN transistor Q2, wherein the control module 24 controls the electric control valve to cut off the refrigerant output from the refrigeration main unit 1 when the hydraulic pressure detected by the second hydraulic pressure sensor 244 is lower than a set value.

The second hydraulic sensor 244 includes a pressure sensitive resistor RF and a second ground resistor R5, the pressure sensitive resistor RF and the second ground resistor R5 are connected in series to form a voltage divider circuit, the pressure sensitive resistor RF is connected to the VCC terminal, and the connection point of the pressure sensitive resistor RF and the second ground resistor R5 is connected to the "-" input terminal of the second voltage comparator N2. The "+" input terminal of the second voltage comparator N2 is connected to the "+" input terminal of the first voltage comparator N1, i.e. the voltage signal inputted from the connection point of the first resistor R1 and the second resistor R2 to the "+" input terminal of the second voltage comparator N2 is set.

The output end of the second voltage comparator N2 is connected to the base of the second NPN transistor Q2, the electronic control valve is a solenoid valve S3, the emitter of the second NPN transistor Q2 is grounded, the collector of the second NPN transistor Q2 is connected to the coil of the solenoid valve S3, and the coil of the solenoid valve S3 is connected to the VCC terminal. When the branch pipe 21 and the backup pipe 22 leak simultaneously, the refrigerant in the main high-pressure pipe 12 is lost to continuously reduce the hydraulic pressure detected by the second hydraulic sensor 244, and at this time, when the output potential of the connection point of the pressure sensitive resistor RF and the second ground resistor R5 is reduced to be lower than the set potential, the solenoid valve S3 is actuated, that is, the electrically controlled valve cuts off the refrigerant output by the refrigeration main machine 1, so that the continuous loss of the refrigerant is reduced, the maintenance workload is reduced, and the pollution of the refrigerant to the environment is reduced. Meanwhile, the second voltage comparator N2 is electrically connected with a power supply control cabinet of the air conditioning system, and when the second voltage comparator N2 outputs a high level, the power supply control cabinet cuts off the power supply of the air conditioning system, so that the potential safety hazard caused by continuous pressurization of the refrigerant when the electric control valve blocks the pipeline is avoided.

The control module 24 is electrically connected with an alarm 243, and the alarm 243 includes a third NPN transistor Q3, a relay KM1, an oscillator, and an alarm lamp. The base of the third NPN type triode Q3 is connected with the output end of the first voltage comparator N1 to receive a switching signal, the emitting electrode of the third NPN type triode Q3 is grounded, the collecting electrode of the third NPN type triode Q3 is connected with one end of the coil of the relay KM1, the other end of the coil of the relay KM1 is connected with the VCC end, the normally open contact KM1-1 of the third NPN type triode Q3 is connected between the VCC end and the input end of the oscillator in series, the output end of the oscillator is.

When the hydraulic pressure detected by the first hydraulic pressure sensor 23 is lower than a set value, the first voltage comparator N1 outputs a switch signal, at the moment, the base of the third NPN type triode Q3 receives a high-level signal, so that the third NPN type triode is conducted, the coil of the relay KM1 is electrified and sends an excitation signal, at the moment, the normally open contact of the relay receives the excitation signal and is closed, the oscillator is electrified and outputs an oscillation signal, the warning lamp is intermittently electrified and generates a flickering phenomenon, and a warning signal is sent out to prompt an operator to maintain the branch pipe 21 in time.

Referring to fig. 4 and 5, the branch pipe 21 is communicated with the circular pipe-shaped injection pipe 3, the opening of the injection pipe 3 is provided with a limiting ring 31, the central axis of the limiting ring 31 is overlapped with the central axis of the opening of the injection pipe 3, and the limiting ring 31 and the injection pipe 3 are fixed in a sealing manner. A cylindrical plug 32 is slidably provided in the injection pipe 3, and the plug 32 is made of hard rubber, thereby improving the sealing property. And the inner diameter of the stop collar 31 is smaller than the inner diameter of the injection pipe 3, thereby preventing the plug 32 from being separated from the injection pipe 3. And set up circular shape annular in the filler pipe 3 to this avoids in embolism 32 gets into branch pipe 21 through filler pipe 3, runs through on the embolism 32 with spacing ring 31 butt side and has seted up a plurality of circular shape water conservancy diversion holes, and a plurality of water conservancy diversion holes are along embolism 32 angular distribution such as circumference.

The injection pipe 3 is detachably connected with an injection pipe 4, the injection pipe 4 is communicated with a sealed tank 43 containing high-pressure refrigerant, the sealed tank 43 is filled with the high-pressure refrigerant, and the hydraulic pressure of the high-pressure refrigerant is higher than that in the total high-pressure pipe 12. The injection pipe 4 is provided with a control valve 44 to facilitate control of discharge of the high-pressure refrigerant. A trigger bolt 41 is fixedly bonded at one end of the injection tube 4, the trigger bolt 41 is cylindrical and is in inserted fit with the limit ring 31, and a through hole 42 communicated with a seal tank 43 is formed in the trigger bolt 41.

When the trigger pin 41 is inserted into the retainer ring 31, the push pin 32 moves to communicate the pilot hole with the through hole 42, thereby connecting the injection pipe 3 with the injection pipe 4 and communicating the seal pot 43 with the branch pipe 21. When the control valve 44 is opened, the high-pressure refrigerant in the sealed tank 43 enters the newly connected branch pipe 21 along the refrigerant injection pipe 4 and the injection pipe 3, so that the newly connected branch pipe 21 is filled with the refrigerant, and the hydraulic pressure of the refrigerant is raised back to the hydraulic pressure level of the total high-pressure pipe 12, thereby avoiding the phenomenon that the high-pressure refrigerant is vaporized due to the rapid reduction of the hydraulic pressure when the switching valve is switched to the branch pipe 21, and further avoiding the influence on the normal circulation of the refrigerant. Meanwhile, the sealing tank 43 compensates the total amount of the refrigerant circulating in the air conditioning system, and the influence of the lost refrigerant on the refrigeration effect is reduced. After the refrigerant is filled, the plug 32 is pressed against the limiting ring 31 under the hydraulic action, so that the flow guide hole on the plug 32, which is opposite to the limiting ring 31, is closed, and the refrigerant is prevented from leaking.

The implementation principle of the embodiment is as follows: when the branch pipe 21 is damaged to cause a refrigerant leakage, the hydraulic pressure in the branch pipe 21 is lowered. At this time, the hydraulic pressure detected by the first hydraulic pressure sensor 23 is lower than a set value, so that the control module 24 controls the switching valve to close the passage between the main high-pressure pipe 12 and the branch pipe 21 and open the passage between the main high-pressure pipe 12 and the standby pipe 22, and at the same time, the control module 24 controls the blocking valve to close the passage between the branch pipe 21 and the output pipe 13 and open the passage between the standby pipe 22 and the output pipe 13, so that the standby pipe 22 is started to replace the branch pipe 21 to realize the circulation of the refrigerant. Meanwhile, the two ends of the branch pipe 21 are kept closed, so that the phenomenon that the circulating refrigerant in the air conditioning system is continuously lost is avoided, and the normal operation of the air conditioning system is kept.

After the branch pipe 21 is damaged and the spare pipe 22 is used, an operator needs to replace the branch pipe 21, detach the branch pipe 21, install a new branch pipe 21, and seal and fix both ends of the new branch pipe 21 with the main high-pressure pipe 12 and the output pipe 13. Then the trigger bolt 41 on the injection tube 4 is inserted into the limiting ring 31 to push the plug 32 to move, so that the diversion hole is communicated with the through hole 42, when the control valve 44 is opened, the high-pressure refrigerant in the sealed tank 43 enters the newly connected branch tube 21 along the injection tube 4 and the injection tube 3, so that the newly connected branch tube 21 is filled with the refrigerant, and the hydraulic pressure of the refrigerant is raised to the hydraulic level of the total high-pressure tube 12. Then, the control valve 44 is closed to pull out the injection pipe 4, and the plug 32 is abutted against the stop collar 31 to prevent the refrigerant from leaking. The switching valve and the blocking valve may then be reset to enable the new branch 21 or to use the new branch 21 as a backup.

If the branch pipe 21 and the backup pipe 22 are damaged at the same time and leakage occurs, the hydraulic pressure in the main high-pressure pipe 12 is reduced, and at this time, the second hydraulic pressure sensor 244 triggers the control module 24 to control the electric control valve to cut off the supply of the refrigerant on the side of the refrigeration main machine 1, so that the loss of the refrigerant is reduced, and the later maintenance is facilitated.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims

1. Control system of cold-storage central air conditioning, its characterized in that: the device comprises a refrigeration host (1), a cooling tower (11), a total high-pressure pipe (12) communicated with the refrigeration host (1) and used for transmitting high-pressure refrigerant, an output pipe (13) communicated with the cooling tower (11) and a protection device (2) arranged between the total high-pressure pipe (12) and the output pipe (13), wherein the protection device (2) comprises a branch pipe (21) communicated with the total high-pressure pipe (12), a standby pipe (22) communicated with the total high-pressure pipe (12), a switching valve used for switching the refrigerant in the total high-pressure pipe (12) to the branch pipe (21) or the standby pipe (22) in a flowing direction, a first hydraulic sensor (23) arranged on the branch pipe (21) and used for detecting the hydraulic pressure of the refrigerant in the branch pipe (21) and a control module (24) electrically connected with the first hydraulic sensor (23) and used for receiving electric signals, one end of the branch pipe (21) and one end of the standby pipe, the output pipe (13) is provided with a blocking valve for switching the output pipe (13) to be communicated with the branch pipe (21) or the standby pipe (22), when the hydraulic pressure detected by the first hydraulic pressure sensor (23) is lower than a set value, the control module (24) controls the switching valve to close the channels of the main high-pressure pipe (12) and the branch pipe (21) and open the channels of the main high-pressure pipe (12) and the standby pipe (22), and meanwhile, the control module (24) controls the blocking valve to close the channels of the branch pipe (21) and the output pipe (13) and open the channels of the standby pipe (22) and the output pipe (13);

the branch pipe (21) is communicated with an injection pipe (3), the injection pipe (3) is detachably connected with an injection pipe (4), the injection pipe (4) is communicated with a sealed tank (43) containing high-pressure refrigerant, and the injection pipe (4) is provided with a control valve (44); the opening part of injection pipe (3) is provided with spacing ring (31), the internal diameter of spacing ring (31) is less than the internal diameter of injection pipe (3), slip is provided with embolism (32) in injection pipe (3), run through with spacing ring (31) butt side on embolism (32) and seted up the water conservancy diversion hole, injection pipe (4) one end is provided with triggers bolt (41), set up through-hole (42) of intercommunication seal pot (43) on triggering bolt (41), trigger bolt (41) and spacing ring (31) grafting cooperation and promote embolism (32) when triggering bolt (41) insert spacing ring (31) in and move so that water conservancy diversion hole and through-hole (42) communicate.

2. The control system of cold storage central air conditioner as claimed in claim 1, wherein: the diverter valve all adopts the three-way valve with blocking the valve, and the import of diverter valve communicates in total high-pressure pipe (12) and its export communicates respectively in branch pipe (21), spare pipe (22), the import of blocking the valve communicates in output tube (13) and its export communicates respectively in branch pipe (21), spare pipe (22).

3. The control system of cold storage central air conditioner as claimed in claim 1, wherein: the control module (24) comprises a detection component (241) and a switch component (242), the detection component (241) comprises a first resistor, a second resistor and a first voltage comparator, the first resistor and the second resistor are connected in series in the same power supply loop, the connection point of the first resistor and the second resistor is connected to the + input end of the first voltage comparator, the output end of the first hydraulic sensor (23) is connected with the-input end of the first voltage comparator, and when the hydraulic pressure of the first hydraulic sensor (23) is lower than a set value, the output end of the first voltage comparator outputs a switch signal.

4. The control system of cold storage central air conditioner as claimed in claim 3, characterized in that: the switching element (242) comprises a first NPN type triode, the base electrode of the first NPN type triode receives a switching signal, the emitting electrode of the first NPN type triode is grounded, the collector electrode of the first NPN type triode is connected with the coil of the electromagnetic valve S1 of the switching valve and the coil of the electromagnetic valve S2 of the blocking valve, and the coil of the electromagnetic valve S1 and the other end of the coil of the electromagnetic valve S2 are connected with a VCC end.

5. The control system of cold storage central air conditioner as claimed in claim 1, wherein: the control module (24) further comprises a second hydraulic pressure sensor (244) used for detecting hydraulic pressure in the main high-pressure pipe (12) and an electric control valve arranged on the side, close to the refrigeration host (1), of the main high-pressure pipe (12), and when the hydraulic pressure measured by the second hydraulic pressure sensor (244) is lower than a set value, the control module (24) controls the electric control valve to cut off refrigerant output by the refrigeration host (1).

6. The control system of cold storage central air conditioner as claimed in claim 3, characterized in that: the control module (24) is electrically connected with an alarm (243), and when the hydraulic pressure detected by the first hydraulic sensor (23) is lower than a set value, the control module (24) controls the alarm (243) to send out an alarm signal.

7. The control system of cold accumulation central air conditioner as claimed in claim 6, wherein: the warning piece (243) comprises a third NPN type triode, a relay and a warning lamp, wherein the base electrode of the third NPN type triode receives a switching signal, the emitting electrode of the third NPN type triode is grounded, the collector electrode of the third NPN type triode is connected to one end of a relay coil, the other end of the relay coil is connected with a VCC end, a normally open contact of the relay coil is connected between the VCC end and the warning lamp in series, and one end of the warning lamp is grounded.

8. The control system of cold accumulation central air conditioner as claimed in claim 7, wherein: the alarm (243) also comprises an oscillator, a normally open contact of the relay coil is connected in series between the VCC end and the input end of the oscillator, and the other end of the alarm lamp is connected to the output end of the oscillator.