CN110542172A - Secondary low-voltage protection device of ultra-high temperature air conditioner - Google Patents
Secondary low-voltage protection device of ultra-high temperature air conditioner Download PDFInfo
- Publication number
- CN110542172A CN110542172A CN201910902519.1A CN201910902519A CN110542172A CN 110542172 A CN110542172 A CN 110542172A CN 201910902519 A CN201910902519 A CN 201910902519A CN 110542172 A CN110542172 A CN 110542172A
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- Prior art keywords
- pressure
- low
- air conditioner
- protector
- pressure controller
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Links
- 230000001012 protector Effects 0.000 claims abstract description 77
- 235000014676 Phragmites communis Nutrition 0.000 claims description 11
- 238000005057 refrigeration Methods 0.000 abstract description 25
- 239000003507 refrigerant Substances 0.000 abstract description 17
- 238000004378 air conditioning Methods 0.000 description 23
- 230000003068 static effect Effects 0.000 description 14
- 238000010586 diagram Methods 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 230000006698 induction Effects 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 239000004020 conductor Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
- F24F11/32—Responding to malfunctions or emergencies
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/89—Arrangement or mounting of control or safety devices
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Air Conditioning Control Device (AREA)
Abstract
The invention discloses a secondary low-pressure protection device of an ultra-high temperature air conditioner, which comprises a pressure controller and a low-pressure protector, wherein the low-pressure protector and the pressure controller are respectively welded on a pipeline of an air conditioner refrigeration system close to a steam return port of a compressor, the low-pressure protector and the pressure controller respectively sense the pressure of a pipeline at the gas return end of the compressor, the low-pressure protector and the pressure controller are integrally connected in series to form a series branch, and two ends of the series branch are respectively connected into an air conditioner start-stop control circuit. The invention can really protect the air conditioner, the air conditioner compressor can not be burnt out due to lack of refrigerant, and the temperature application range of the air conditioner is expanded.
Description
Technical Field
The invention relates to the field of air conditioner protection devices, in particular to a secondary low-voltage protection device of an ultrahigh-temperature air conditioner.
Background
The working principle of the air-conditioning refrigeration system is shown in fig. 1, low-temperature and low-pressure gaseous refrigerant in the air-conditioning refrigeration system is sucked by a compressor and compressed into high-temperature and high-pressure gas, the high-temperature and high-pressure gas is cooled into high-pressure liquid in an outdoor heat exchanger, the high-pressure liquid is throttled and reduced in pressure by an expansion valve and flows into an indoor heat exchanger, the low-pressure liquid refrigerant is evaporated and absorbs heat to cool the indoor, the evaporated refrigerant gas is sucked by the compressor again, and the operation is repeated so as to achieve the.
the core component of the air-conditioning refrigeration system is a compressor, the compressor can suck low-pressure vapor refrigerant of the air-conditioning refrigeration system and discharge high-temperature high-pressure gas refrigerant, when the air-conditioning refrigeration system leaks, the refrigeration effect of the air conditioner can be influenced, the compressor can be burnt out due to long-time idling of the air-conditioning compressor, in order to avoid the condition, a low-pressure protector is usually arranged on a pipeline of the air-conditioning refrigeration system, which is close to a vapor return port of the compressor, when the internal pressure of the air-conditioning refrigeration system due to refrigerant leakage is lower than the set value of the low-pressure protector, the low-pressure protector is disconnected, because a control line of the low-pressure protector is connected in series to a starting control circuit of the air conditioner, the air.
At present, when an ultra-high temperature air conditioner works in an external environment of 40-80 ℃ for a long time, a low-pressure switch of an air conditioning refrigeration system cannot be disconnected, the air conditioner can work normally, however, sometimes the air conditioner will perform cooling operation in an outdoor environment below 40 ℃, the pressure of the cooling system of the air conditioner is often too low due to the good condensing capacity of the outdoor unit at low ambient temperature, especially for the air conditioner filled with low-pressure cooling (such as R142b refrigerant), because the ultra-high temperature air conditioner is filled with low-pressure refrigeration (R142b refrigerant), the internal pressure of the air-conditioning refrigeration system is lower than the set value of the low-pressure protector at a lower outdoor environment temperature, so that the switch of the low-pressure protector is switched off, the air conditioner stops working, however, the actual air conditioner refrigerating system does not leak, the air conditioner does not lack a refrigerant, the air conditioner should continue to perform refrigerating operation in the environment, and the disconnection of the low-pressure protector belongs to misoperation. Although the low-pressure protector is disconnected to avoid the phenomenon of burning out the compressor, the low-pressure fault of the air conditioner refrigerating system is misjudged, and the normal work of the air conditioner is influenced because the actual air conditioner does not lack a refrigerant.
The invention aims to provide a secondary low-voltage protection device of an ultra-high temperature air conditioner, which aims to solve the problems that the low-voltage fault of the air conditioner is misreported at the low ambient temperature and the air conditioner cannot work normally in the prior art, and broadens the range of the low ambient temperature use temperature of the ultra-high temperature air conditioner.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
The utility model provides an ultra-high temperature air conditioner second grade low pressure protection device which characterized in that: the low-pressure protector and the pressure controller are respectively used for sensing the pressure at different positions of a pipeline at the air return end of the compressor through respective pressure sensing ends, the low-pressure protector and the pressure controller are integrally connected in series to form a series branch, two ends of the series branch are respectively connected with an air conditioner start-stop control circuit, and the pressure controller controls the low-pressure protector to be connected into or not connected with the air conditioner start-stop control circuit.
The two-stage low-voltage protection device of the ultra-high temperature air conditioner is characterized in that: the low-pressure protector is provided with two cables, the pressure controller is provided with three stationary contacts and a movable reed, one end of the movable reed is connected with the first stationary contact, the other end of the movable reed is in contact with the second stationary contact and can move to be separated from the second stationary contact and the third stationary contact, one cable of the low-pressure protector is connected with the second stationary contact of the pressure controller, the other cable of the low-pressure protector is connected with the third stationary contact of the pressure controller, a series branch is formed by connecting the other cable of the low-pressure protector with the third stationary contact of the pressure controller, the first stationary contact of the pressure controller is connected into an air conditioner starting and stopping control circuit, a lead is led out between the other cable of the low-pressure protector and the third stationary contact of the pressure controller to be connected into the air conditioner starting and stopping control circuit, and.
The two-stage low-voltage protection device of the ultra-high temperature air conditioner is characterized in that: the pressure sensing ends of the low-pressure protector and the pressure controller are respectively communicated to a pipeline at the air return end of the compressor in a bypass mode.
The two-stage low-voltage protection device of the ultra-high temperature air conditioner is characterized in that: the pressure sensing end of the pressure controller is positioned between the pressure sensing end of the low-pressure protector and the air return end of the compressor.
The inside spring leaf that has a perception pressure of low pressure protector, the head has two cables, two cables one end respectively stretch into low pressure protector inside and be connected with electric connection contact respectively, sensing pressure when low pressure protector, pressure is used on the spring leaf and when exceeding its set elastic pressure value, the spring leaf is gone up to being connected the contact with two electricity respectively, make two cable conductor switch-ons of low pressure protector head, constitute the circuit route, when no pressure is used on the spring leaf or when pressure does not exceed its set elastic pressure value, two cable conductor disconnection of low pressure protector head, constitute the circuit route.
The pressure controller is internally provided with a movable contact spring for sensing pressure and three static contacts, one end of the movable contact spring is connected with the first static contact, the other end of the movable contact spring is in electric contact with the second static contact, when the pressure controller does not sense the pressure or the pressure does not exceed the set elastic pressure value of the movable contact spring, the movable contact spring is connected with the first static contact and the second static contact to form a passage, and when the pressure acts on the movable contact spring, one end of the movable contact spring can be in electric contact with the third static contact to form a passage.
In the invention, when the pressure of the air conditioner system is lower due to lack of refrigerant, and the pressure of the air conditioner system is lower than the set values of the pressure controller and the low-pressure protector, the spring leaf in the low-pressure protector keeps resetting, and at the moment, the two cables of the low-pressure protector are disconnected. The movable reed in the pressure controller also keeps resetting, the protector circuit formed by the movable reed and the pressure controller is integrally disconnected, and the air conditioner can be controlled to stop at the moment to protect the air conditioner.
When the air conditioner works at a lower outdoor environment temperature, the pressure value of the air conditioning system is lower than the set value of the pressure controller, the movable spring piece of the pressure controller can be kept to reset, the pressure of the air conditioning system at the position of the low-pressure protector is higher than the pressure of the air conditioning system at the position of the pressure controller, the spring piece of the low-pressure protector is in an upward spring state, two cables of the low-pressure protector are in a switch-on state, the air conditioner cannot stop working due to low system pressure at the position of the pressure protector, and the low-pressure protector plays a role in protecting the air conditioning refrigeration system independently. When the real refrigerant of air conditioner leaks, when refrigerating system low pressure (the pressure of low pressure protector position) was less than the set pressure value of low pressure protector, two cables of low pressure protector just can break off, and the air conditioner stop work can really play the guard action to the air conditioner like this, can not make the air conditioner burn out because of lacking the refrigerant, can not influence the use under the low ambient temperature of air conditioner yet.
The invention has the following beneficial effects:
1) The risk that the super air conditioner is shut down when used in a low-temperature external environment is avoided, and the temperature range of the air conditioner used in a low environment temperature is widened.
2) The risk of long-term idling of the air condition compressor is avoided, and the service life of the air condition compressor is prolonged.
Drawings
Fig. 1 is a schematic diagram of the operation of a prior art air conditioner refrigeration system.
Fig. 2 is a schematic structural diagram of the low pressure protector.
fig. 3 is a schematic diagram of the structure of the pressure controller.
Fig. 4 is a schematic diagram of the structural principle of the present invention.
Detailed Description
The invention is further illustrated with reference to the following figures and examples.
As shown in fig. 2-4, an ultra-high temperature air conditioner second level low pressure protection device, including low pressure protector 1 and pressure controller 2, low pressure protector 1, pressure controller 2 respectively through the different position pressure of pressure induction end sensing compressor 3 return air end pipeline 4 separately, low pressure protector 1 and pressure controller 2 wholly concatenate and constitute the series branch, the air conditioner opens and stops in the control circuit respectively to be connected at series branch both ends, control low pressure protector 1 by pressure controller 2 and insert or not insert the air conditioner and open and stop the control circuit.
As shown in fig. 2, a spring plate 5 for sensing pressure is arranged in the low-pressure protector 1, the head of the low-pressure protector is provided with two cable wires A, B, one end of each of the two cable wires A, B extends into the low-pressure protector 1 and is respectively connected with an electric connection contact, when the low-pressure protector 1 senses pressure and the pressure acts on the spring plate 5 and exceeds the set elastic pressure value thereof, the spring plate 5 springs up to be respectively contacted with the two electric connection contacts, so that the two cable wires A, B at the head of the low-pressure protector 1 are connected to form a circuit path, and when no pressure acts on the spring plate 5 or the pressure does not exceed the set elastic pressure value thereof, the two cable wires A, B at the head of the low-pressure protector 1 are disconnected.
As shown in fig. 3, a movable contact spring 6 for sensing pressure is arranged in the pressure controller 2, and the pressure controller has three stationary contacts a, b, and c, wherein one end of the movable contact spring 6 is connected to the first stationary contact a, and the other end of the movable contact spring 6 is in electrical contact with the second stationary contact b, when the pressure controller 2 does not sense pressure or the pressure does not exceed the set elastic pressure value of the movable contact spring 6, the movable contact spring 6 is connected to the first stationary contact a and the second stationary contact b to form a passage, and when pressure acts on the movable contact spring 6, one end of the movable contact spring 6 can be in electrical contact with the third stationary contact c to form a passage.
In the invention, one cable A of a low-pressure protector 1 is connected with a second static contact B of a pressure controller 2, the other cable B of the low-pressure protector 1 is connected with a third static contact c of the pressure controller 2, so that a series branch is formed, the first static contact a of the pressure controller 2 is connected into an air conditioner starting and stopping control circuit through a line E, and a line F is led out between the other cable B of the low-pressure protector 1 and the third static contact c of the pressure controller 2 and is connected into the air conditioner starting and stopping control circuit, so that the connection of the series branch and the air conditioner starting and stopping control circuit is realized.
The pressure sensing ends of the low-pressure protector 1 and the pressure controller 2 are respectively communicated to a pipeline of an air return end 4 of the compressor 3 in a bypass mode. And the pressure sensing end of the pressure controller 2 is positioned between the pressure sensing end of the low-pressure protector 1 and the air return end of the compressor 3.
The invention welds the pressure controller 2 on the return pipe close to the return port of the air-conditioning compressor, the pressure controller 2 can set the pressure value (0.02MPa), welds the low pressure protector 1 on the return pipe (evaporator outlet) away from the return port of the compressor by a certain distance, the set pressure value of the low pressure protector 1 is a fixed value (0.02 MPa).
When the system pressure is higher than the fixed set pressure value of the low-pressure protector 1, the cables A and B of the low-pressure protector 1 are switched on, and the cables A and B are switched off. The pressure controller 2 is connected by a cable according to a graph 4, a control line is connected to a starting control circuit of the air conditioner in series, when the air conditioner refrigeration system does not lack a refrigerant, the internal pressure of the air conditioner refrigeration system is greater than a set pressure value (such as 0.02MPa) of the pressure controller 2, a movable spring 6 of the pressure controller 2 is sprung, the movable spring 6 of the pressure controller 2 enables a static contact a and a static contact c to be connected, a cable A and a cable B are short-circuited and used for being directly connected between a circuit E and a circuit F which are connected with the air conditioner starting and stopping control circuit, and the air conditioner can normally refrigerate.
When the temperature of the air conditioning refrigeration system is too low due to the external use environment of the air conditioner, and the internal pressure (the induction position of the pressure controller) of the air conditioning refrigeration system is smaller than a set pressure value (such as 0.02MPa), the movable reed 6 of the pressure controller 2 is disconnected with the fixed contact c, the movable reed 6 of the pressure controller 2 is reset, the movable reed 6 enables the fixed contacts a and b to be connected, and the low-pressure protector 1 is connected to a starting control circuit of the air conditioner in series. When the refrigerant flows in the pipeline of the refrigeration system, because of the pressure drop of the resistance of the pipeline, the pressure of the refrigeration system at the position of the low-pressure protector 1 is far away from the position of the compressor at the moment, the pressure of the refrigeration system at the position is larger than the system pressure at the position of the pressure controller 2 close to the steam return port of the compressor, when the internal pressure of the air-conditioning refrigeration system (the induction position of the pressure controller 2) is smaller than the set pressure value (0.02MPa) of the pressure controller 2, the static contact a and the static contact B of the pressure controller 2 are connected, at the moment, if the pressure of the refrigeration system at the position of the low-pressure protector 1 is larger than the system pressure at the position of the pressure controller 2 and is higher than the set pressure value (0.02MPa) of the low-pressure protector, the spring leaf 5 of the low-pressure protector 1 is sprung up, the cable A and the cable B are connected, the passage between circuits E, F of the start-stop control circuit of the air, the air conditioner cannot normally work because the pressure value of the air return port system of the air conditioner compressor is lower than the set pressure value (0.02MPa), and the application range of the ultra-high temperature air conditioner in the low-temperature environment is widened.
In addition, when the air-conditioning refrigeration system is lack of refrigerant due to leakage, when the pressure inside a pipeline of the air-conditioning refrigeration system (at the position of the low-pressure protector 1) is smaller than the set pressure value (0.02MPa) of the low-pressure protector 1, the pressure is also smaller than the set pressure value (0.02MPa) of the pressure controller 2, the movable spring 6 of the pressure controller 2 and the spring 5 of the low-pressure protector 1 are reset, the circuit E, F of the air-conditioning start-stop control circuit is disconnected, the fixed contact c and the fixed contact a are disconnected, finally, the circuit between the circuits E, F of the air-conditioning start-stop control circuit is disconnected, the air-conditioning compressor stops running, and the.
Fig. 4 of the invention only exemplifies the application of the secondary low-voltage protection device to the ultra-high temperature air conditioner, and the invention can be applied to most household air conditioners and military and civil special air conditioners. Therefore, the above embodiments are not limited to the protection scope of the present invention, and all modifications or variations based on the basic idea of the present invention belong to the protection scope of the present invention.
Claims (4)
1. The utility model provides an ultra-high temperature air conditioner second grade low pressure protection device which characterized in that: the low-pressure protector and the pressure controller are respectively used for sensing the pressure at different positions of a pipeline at the air return end of the compressor through respective pressure sensing ends, the low-pressure protector and the pressure controller are integrally connected in series to form a series branch, two ends of the series branch are respectively connected with an air conditioner start-stop control circuit, and the pressure controller controls the low-pressure protector to be connected into or not connected with the air conditioner start-stop control circuit.
2. The secondary low-pressure protection device of the ultra-high temperature air conditioner according to claim 1, characterized in that: the low-pressure protector is provided with two cables, the pressure controller is provided with three stationary contacts and a movable reed, one end of the movable reed is connected with the first stationary contact, the other end of the movable reed is in contact with the second stationary contact and can move to be separated from the second stationary contact and the third stationary contact, one cable of the low-pressure protector is connected with the second stationary contact of the pressure controller, the other cable of the low-pressure protector is connected with the third stationary contact of the pressure controller, a series branch is formed by connecting the other cable of the low-pressure protector with the third stationary contact of the pressure controller, the first stationary contact of the pressure controller is connected into an air conditioner starting and stopping control circuit, a lead is led out between the other cable of the low-pressure protector and the third stationary contact of the pressure controller to be connected into the air conditioner starting and stopping control circuit, and.
3. The secondary low-pressure protection device of the ultra-high temperature air conditioner according to claim 1, characterized in that: the pressure sensing ends of the low-pressure protector and the pressure controller are respectively communicated to a pipeline at the air return end of the compressor in a bypass mode.
4. The secondary low-pressure protection device of the ultra-high temperature air conditioner according to claim 3, characterized in that: the pressure sensing end of the pressure controller is positioned between the pressure sensing end of the low-pressure protector and the air return end of the compressor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910902519.1A CN110542172B (en) | 2019-09-24 | 2019-09-24 | Two-stage low-voltage protection device of ultra-high temperature air conditioner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910902519.1A CN110542172B (en) | 2019-09-24 | 2019-09-24 | Two-stage low-voltage protection device of ultra-high temperature air conditioner |
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| CN110542172A true CN110542172A (en) | 2019-12-06 |
| CN110542172B CN110542172B (en) | 2024-03-29 |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5315653A (en) * | 1976-07-28 | 1978-02-13 | Mitsubishi Electric Corp | Control circuit of air conditioner |
| CN102679506A (en) * | 2011-03-11 | 2012-09-19 | 上海日立电器有限公司 | Leakage processing device for flammable refrigerant in air-conditioning system |
| CN205448180U (en) * | 2015-11-24 | 2016-08-10 | 上海海立特种制冷设备有限公司 | Bridge crane air conditioner prevents that compressor starts protection device of low pressure |
| CN205980497U (en) * | 2016-08-24 | 2017-02-22 | 武汉克莱美特环境设备有限公司 | Compressor's shutdown protection system |
| CN107053997A (en) * | 2016-12-22 | 2017-08-18 | 重庆长安汽车股份有限公司 | Automobile air-conditioning evaporator defroster and method |
| CN108344122A (en) * | 2018-04-12 | 2018-07-31 | 合肥天鹅制冷科技有限公司 | High-temperature air conditioner cryogenic refrigeration operating system |
| CN210892055U (en) * | 2019-09-24 | 2020-06-30 | 合肥天鹅制冷科技有限公司 | Secondary low-voltage protection device of ultra-high temperature air conditioner |
-
2019
- 2019-09-24 CN CN201910902519.1A patent/CN110542172B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5315653A (en) * | 1976-07-28 | 1978-02-13 | Mitsubishi Electric Corp | Control circuit of air conditioner |
| CN102679506A (en) * | 2011-03-11 | 2012-09-19 | 上海日立电器有限公司 | Leakage processing device for flammable refrigerant in air-conditioning system |
| CN205448180U (en) * | 2015-11-24 | 2016-08-10 | 上海海立特种制冷设备有限公司 | Bridge crane air conditioner prevents that compressor starts protection device of low pressure |
| CN205980497U (en) * | 2016-08-24 | 2017-02-22 | 武汉克莱美特环境设备有限公司 | Compressor's shutdown protection system |
| CN107053997A (en) * | 2016-12-22 | 2017-08-18 | 重庆长安汽车股份有限公司 | Automobile air-conditioning evaporator defroster and method |
| CN108344122A (en) * | 2018-04-12 | 2018-07-31 | 合肥天鹅制冷科技有限公司 | High-temperature air conditioner cryogenic refrigeration operating system |
| CN210892055U (en) * | 2019-09-24 | 2020-06-30 | 合肥天鹅制冷科技有限公司 | Secondary low-voltage protection device of ultra-high temperature air conditioner |
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| CN110542172B (en) | 2024-03-29 |
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