Abstract:
A compressor includes two parallel arranged primary cylinders and a secondary cylinder arranged in the downstream of the two primary cylinders. The secondary cylinder includes a cylinder body and a sliding vane. The sliding vane is arranged inside the cylinder body. A locking part is used for locking and unlocking the sliding vane. The locking part is clamped with and separated from the sliding vane. When the sliding vane is in the locking position, the sliding vane is locked in a seal cavity inside the secondary cylinder, and the locking end of the locking part extends to the side at which the secondary cylinder is located. The compressor can be switched between a single-stage mode and a double-stage mode. In the condition of light load, energy efficiency can be improved and the waste of energy sources is avoided. An air conditioning system and compressor control method are also disclosed.

Description:
FIELD OF THE INVENTION 
       [0001]    The present application relates to heat exchange systems, and more specifically to a compressor, an air conditioning system, and a method of controlling a compressor. 
       BACKGROUND OF THE INVENTION 
       [0002]    With increasingly strict requirement of national energy efficiency index, the existing two-stage enthalpy-increasing compressors solve the problem of insufficient heating capacity at low temperatures by air supplying and enthalpy increasing, thereby increasing heating capacity of an air-conditioning system. 
         [0003]    A two-stage enthalpy-increasing compressor in the prior art comprises one secondary cylinder and two primary cylinders that supply air to the secondary cylinder. Under a heavy load working condition (e.g., nominal refrigeration, nominal heating, national standard working condition, low-temperature working condition, etc.), in the case of a relative large pressure ratio, two-stage compression may effectively allocate the pressure ratio, such that the primary-stage cylinder and the secondary-stage cylinder can operate efficiently. However, under a low load working condition (e.g., IPLV working condition, intermediate working condition, etc.), in the case of a relatively lower pressure ratio, pressure-ratio allocation by two-stage compression will be less efficient, which easily causes a too small pressure ratio allocated to the first-stage cylinder or the secondary-stage cylinder; at this point, the cylinder essentially becomes one resistive component with a gas exhaust valve disc, thereby reducing compressor energy efficiency. 
         [0004]    Due to not having a single-stage working mode, the two-stage compressor in the prior art cannot switch between the two-stage working mode and the single-stage working mode, resulting in a low energy-efficiency of the compressor in a low load working condition. 
       SUMMARY OF THE INVENTION 
       [0005]    The present application intends to provide a compressor, an air-conditioning system, and a method of controlling a compressor, so as to solve the low energy-efficiency issue of the compressor in a low load working condition. 
         [0006]    In order to solve the technical problem above, according to one aspect of the present application, there is provided a compressor, comprising: two primary-stage cylinders disposed in parallel; a secondary cylinder disposed downstream of the two primary-stage cylinders, comprising a cylinder body and a sliding vane provided inside the cylinder body; and a locking part for locking or unlocking the sliding vane, the locking part being engaged to or disengaged from the sliding vane, such that when the sliding vane is in a locked position, the sliding vane is locked within a closed cavity of the secondary-stage cylinder, and a locking end of the locking part protrudes towards the secondary-stage cylinder. 
         [0007]    Further, the compressor further comprises an enthalpy-increasing component which comprising: an enthalpy-increasing cavity, the secondary cylinder being in communication with the secondary-stage cylinder; each of the two primary-stage cylinders being in communication with the enthalpy-increasing cavity, and the locking part being slidably disposed within the enthalpy-increasing cavity, and a locking end of the locking part protruding towards the sliding vane; and an air supply part for supplying air to the secondary-stage cylinder via the enthalpy-increasing cavity, the air supply part being connected to the enthalpy-increasing cavity. 
         [0008]    Further, the locking part comprises a locking pin, a first end of the locking pin being the locking end, a first end of the locking pin having an engaging groove that is engaged to or disengaged from the sliding vane. 
         [0009]    Further, the locking part comprises a locking pin, a first end of the locking pin serves as the locking end, the sliding vane having a locking mating part matable with the locking end, the locking end is able to lock or unlock the locking mated part. 
         [0010]    Further, a first end of the locking pin has a locking bump, and the locking mating part serves as a locking recess, and the locking bump is able to lock or unlock the locking recess. 
         [0011]    Further, the compressor further comprises a resetting element for keeping the locking part at a locked position, the resetting element being disposed within the enthalpy-increasing cavity and at a reset end of the locking part, the reset end being disposed opposite to the locking end. 
         [0012]    Further, the reset end has a receiving recess, and at least part of the resetting element being disposed within the receiving recess. 
         [0013]    Further, the enthalpy-increasing component is also provided with an exhaust port, the compressor also comprises a control valve, the exhaust port being in communication with the enthalpy-increasing cavity, and the control valve controlling opening and closing states of the exhaust port. 
         [0014]    According to another aspect of the application, there is an air conditioning system, comprising a compressor as above mentioned. 
         [0015]    According to another aspect of the application, there is a compressor controlling method, comprising: controlling a locking part to engage to or disengage from a sliding vane of a secondary-stage cylinder so as to lock or unlock the sliding vane, such that when the sliding vane is engaged with the locking part, the sliding vane is locked within a closing cavity of the cylinder of the secondary-stage cylinder, to offload the secondary-stage cylinder and cause the two primary-stage cylinders to work. 
         [0016]    Further, according to a magnitude relationship between an air pressure of the secondary-stage cylinder and an air pressure in the two primary-stage cylinders, controlling the locking part to engage with or disengage from the secondary-stage cylinder, so as to lock or unlock the secondary-stage cylinder, an air pressure of the secondary-stage cylinder being a sum of air pressures of the two one-secondary cylinders and an air pressure of an air supply part. 
         [0017]    Further, when the air supply part supplies air, the air pressure in the secondary-stage cylinder is larger than the air pressures in the two primary-stage cylinders; the locking part moves far away from the secondary-stage cylinder; the locking part unlocks the sliding vane of the secondary-stage cylinder; the secondary-stage cylinder is in a working state; and when the air supply part is closed, the air pressure within the secondary-stage cylinder is equal to the air pressures within the two primary-stage cylinders; the locking part moves towards the secondary-stage cylinder under a resetting action force of the resetting element; the locking part locks the sliding vane of the secondary-stage cylinder, and the secondary-stage cylinder is in an offloaded state. 
         [0018]    Further, when the air supply part supplies air, the control valve controls the exhaust gas to close, so as to make the secondary-stage cylinder exhaust; and when the air supply part is closed, the control valve controls the exhaust port to open so as to make the enthalpy-increasing cavity exhaust. 
         [0019]    In the present application, there exist two primary-stage cylinders that are arranged in parallel; the secondary-stage cylinder is disposed downstream of the two primary-stage cylinders; the secondary-stage cylinder comprises a cylinder body and a sliding vane that is disposed inside the cylinder body; when the sliding vane is provided inside a locked position, the sliding vane is locked within the closed cavity of the secondary-stage cylinder; a locking end of the locking part protrudes towards the secondary-stage cylinder; the locking part is engaged with or disengaged from the secondary-stage cylinder for locking or unlocking the sliding vane. Due to providing of the locking part, disengagement of the locking part from the sliding vane may unlock the secondary-stage cylinder, such that the compressor switches to run in a two-stage mode; or engagement of the locking part with the sliding vane may lock the secondary-stage cylinder, such that the compressor switches to run in a single-stage mode; in this way, energy-efficiency may be enhanced when the compressor works in a low load working condition, which avoids energy waste. Because the compressor enables switching between two-stage and single-stage modes, operation reliability of the compressor is enhanced, such that the compressor may have a high energy-efficiency in various working conditions. 
     
    
     
       BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
         [0020]    The drawings illustrated here are for providing further understanding of the present application and thus constitute part of the present application. The exemplary embodiments of the present application and depictions thereof are for interpreting the present application, not constituting improper limitations of the present application. In the drawings: 
           [0021]      FIG. 1  is a schematic diagram of a structure of a compressor in the present application; 
           [0022]      FIG. 2  is a schematic diagram of a working state of a locking part of the present application in a locked position; 
           [0023]      FIG. 3  is a schematic diagram of a working state of a locking part of the present application in an unlocked position; 
           [0024]      FIG. 4  is a principle diagram of a compressor operation mode when a locking part of the present application is in a locked position; and 
           [0025]      FIG. 5  is a principle diagram of a compressor operation mode when a locking part of the present application is in an unlocked position. 
       
    
    
       [0026]    Reference numerals in the accompanying drawings:  10 . Primary-stage cylinder;  20 . Secondary-stage cylinder;  21 . Cylinder body;  22 . Sliding vane;  30 . Locking part;  31 . Locking end;  31   a.  Locking bump;  32 . Resetting end;  41 : Enthalpy-increasing cavity;  42 . Air supply part;  42   a . Air supply valve;  50 . Control valve;  60 . Resetting element;  70 . Crankshaft;  71 . Upper flange;  72 . Upper partition plate;  73 . Middle partition plate;  74 . Lower partition plate;  75 . Lower flange;  76 . Cover plate;  77 . Lower roller;  78 . Middle roller;  79 . Secondary-stage cylinder roller;  80 . Liquid dispenser. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]    Hereinafter, embodiments of the present application may be described in detail with reference to the accompanying drawings. However, the present application may be implemented in a plurality of various manners limited and covered by the claims. 
         [0028]    As a first aspect of the present application, there is provided a compressor. As shown in  FIGS. 1-5 , the compressor comprises a primary-stage cylinder  10 , a secondary-stage cylinder  20 , and a locking part  30  adapted to lock or unlock a sliding vane  22 ; there exist two primary-stage cylinders  10  that are provided in parallel; the secondary-stage cylinder  20  is disposed downstream of the two primary-stage cylinders  10 , and comprises a cylinder body  21  and a sliding vane  22  that is provided inside the cylinder body  21 . The locking part  30  is engaged to or disengaged from the sliding vane  22 , such that when the sliding vane  22  is in a locked position, the sliding vane  22  is locked within a closed cavity of the secondary-stage cylinder  20 . Besides, a locking end  31  of the locking part  30  protrudes towards the secondary-stage cylinder  20 . Due to providing of the locking part  30 , disengagement of the locking part  30  from the sliding vane  22  may unlock the secondary-stage cylinder  20 , such that the compressor switches to run in a two-stage mode; or engagement of the locking part  30  with the sliding vane  22  could lock the secondary-stage cylinder  20 , such that the compressor switches to run in a single-stage mode. In this way, energy-efficiency may be improved when the compressor works in a low load, which avoids energy waste. Because the compressor enables switching between two-stage and single-stage modes, operation reliability of the compressor is enhanced, such that the compressor have a high energy-efficiency in various working conditions. 
         [0029]    The compressor in the present application further comprises an enthalpy-increasing component that comprises: an enthalpy-increasing cavity  41  and an air supply part  42  that supplies air to the secondary-stage cylinder  20 , the secondary-stage cylinder  20  being in communication with the enthalpy-increasing cavity  41 . Each of the two primary-stage cylinders  10  is in communication with the enthalpy-increasing cavity  41 . A locking part  30  is slidably provided in the enthalpy-increasing cavity  41 , and the locking end  31  of the locking part  30  is protruding towards the secondary-stage cylinder  20 . The air supply part  42  is connected to the enthalpy-increasing cavity  41 . Due to providing of the air supply part  42 , an air supply operation may be performed to the secondary-stage cylinder  20 , thereby guaranteeing working reliability of the secondary-stage cylinder  20 , such that the compressor can satisfy the working requirement of heavy load. Because the locking part  30  is slidably disposed within the enthalpy-increasing cavity  41 , and both of the primary-stage cylinders  10  and secondary-stage cylinder  20  are in communication with the enthalpy-increasing cavity  41 . A pressure difference between the secondary-stage cylinder  20  and the primary-stage cylinders  10  may control the position of the locking part  30  within the enthalpy-increasing cavity  41 , thereby engaging or disengaging the locking part  30  with or from the secondary-stage cylinder  20 . 
         [0030]    Preferably, the air supply valve  42   a  controls on or off of the air supply part  42 . 
         [0031]    The locking part  30  in the present application comprises a locking pin. A first end of the locking pin serves as a locking end  31 , and the sliding vane  22  has a locking mating part matable with the locking end  31 . The locking end  31  may lock or unlock the locking mated part. Because the sliding vane  22  has a locking mated part matable with the locking end  31 , reliability of locking between the locking pin and the sliding vane  22  is guaranteed. 
         [0032]    In the preferred embodiments shown in  FIGS. 2 and 3 , a first end of the locking pin has a locking bump  31   a,  the locking mating part is a locking recess, the locking bump  31   a  may lock or unlock the locking recess. When the locking bump  31   a  projects into the locking recess, the locking pin locks the sliding vane  22 . When the locking bump  31   a  retracts from the inside of the locking recess, the locking pin unlocks the sliding vane  22 . 
         [0033]    In a preferred embodiment that is not shown, the locking part  30  comprises a locking pin, a first end of the locking pin severs as a locking end  31 , a first end of the locking pin has an engaging groove that is engaged to or disengaged from the sliding vane  22 . When the engaging groove of the locking pin is engaged with a surface of the sliding vane  22 , the locking pin locks the sliding vane  22 ; when the engaging groove of the locking pin is disengaged from the sliding vane  22 , the sliding vane  22  is unlocked. 
         [0034]    The compressor in the present application further comprises a resetting element  60  for keeping the locking part  30  at a locked position, the resetting element  60  being disposed within the enthalpy-increasing cavity  41  and at a reset end  32  of the locking part  30 , the reset end  32  being disposed opposite to the locking end  31 . Due to providing of the resetting element  60 , the resetting element  60  always provides a reset acting force to the locking part  30 , such that the locking part  30  can be maintained at the locking position. When the air pressure of the secondary-stage cylinder  20  is far larger than the air pressure within the primary-stage cylinder  10 , the locking part  30  will overcome the reset acting force of the resetting element  60  so as to be disengaged from the secondary-stage cylinder  20 . 
         [0035]    In the preferred embodiment shown in  FIGS. 2 and 3 , the resetting end  32  has a receiving recess, at least part of the resetting element being disposed within the receiving recess. Because the resetting end  32  has the receiving recess, when the locking part  30  is located at an unlocked position, the resetting element  60  may be retracted back into the receiving recess, thereby avoiding that the resetting element  60  and the locking part  30  occupy a too much space. Meanwhile, connection reliability between the resetting element  60  and the locking part  30  is also guaranteed. 
         [0036]    The enthalpy-increasing component in the present application further comprises an exhaust port; the compressor further comprises a control valve  50 ; the exhaust port is in communication with the enthalpy-increasing cavity  41 ; the control valve  50  controls on and off states of the exhaust port. Because the control valve  50  may control the on and off states of the exhaust port, the usage state of the exhaust port may be switched through the control valve  50  based on whether the secondary-stage cylinder  20  needs to work, thereby enhancing usage reliability of the compressor. Preferably, the control valve  50  is an electromagnetic valve. 
         [0037]    The compressor in the present application further comprises a crankshaft  70 , an upper flange  71 , an upper partition plate  72 , a middle partition plate  73 , a lower partition plate  74 , a lower flange  75 , a cover plate  76 , a lower roller  77 , a middle roller  78 , and a secondary-stage cylinder roller  79 , wherein the upper partition plate  72  and the middle partition plate  73  are parts of the enthalpy-increasing component and form the enthalpy-increasing cavity  41 . The assembly relationships between respective components along a length direction of the crankshaft  70  are sequentially: the upper flange  71 , the secondary-stage cylinder  20 , the upper partition plate  72 , the middle partition plate  73 , one primary-stage cylinder  10 , the lower partition plate  74 , another primary-stage cylinder  10 , the lower flange  75 , and the cover plate  76 , wherein the lower roller  77  is disposed within the another primary-stage cylinder  10 , the middle roller  78  is disposed within the one first-primary cylinder  10 , and the secondary-stage cylinder roller  79  is disposed within the secondary-stage cylinder  20 . 
         [0038]    The compressor in the present application further comprises a liquid dispenser  80 , and the liquid dispenser  80  is connected to two primary-stage cylinders  10 , for supplying air to the two primary-stage cylinders  10 . 
         [0039]    As a second aspect of the present application, there is provided an air-conditioning system. The air-conditioning system comprises a compressor as mentioned above. Because the compressor in the present application has a function of switching between two-stage and single-stage working modes, it may satisfy use requirements of the air-conditioning system under various working conditions and effectively guaranteeing working reliability of the compressor and the air-conditioning system, such that the compressor and the air-conditioning system can have a high energy-efficiency under various working conditions. 
         [0040]    As a third aspect of the present application, there is provided a compressor controlling method. As shown in  FIGS. 4 and 5 , the compressor controlling method comprises: controlling the locking part to engage to or disengage from a secondary-stage cylinder so as to lock or unlock a sliding vane  22 , such that when the sliding vane  22  is engaged with the locking part  30 , the sliding vane  22  is locked within the closing cavity of the cylinder  21  of the secondary-stage cylinder  20 , to offload the secondary-stage cylinder  20  and cause the two primary-stage cylinders  10  to work. Because the working mode of the compressor may be changed by changing the mating condition of the locking part  30  and the slide vane  22 , this enables the compressor to effectively switch between two-stage and single-stage modes, and thus operation reliability of the compressor is enhanced, such that the compressor have a high energy-efficiency in various working conditions. 
         [0041]    Preferably, based on magnitude relationship between the air pressure in the secondary-stage cylinder  20  and two primary-stage cylinders  10 , the locking part  30  is controlled to be engaged with or disengaged from the secondary-stage cylinder  20  so as to lock or unlock the secondary-stage cylinder  20 ; the air pressure in the secondary-stage cylinder  20  is a sum of the air pressure in the two primary-stage cylinders  10  and the air pressure in the air supply part  42 . Because pressure difference exists between the secondary-stage cylinder  20  and the primary-stage cylinder  10  in some working conditions, by controlling the position of the locking part  30  based on the pressure relationship between the secondary-stage cylinder  20  and the first-stage cylinder  10 , the locking part  30  unlocks or locks the secondary-stage cylinder  20 , such that the compressor has a function of switching between the two-stage and single-stage working modes. 
         [0042]    As shown in  FIG. 4 , when the air supply part  42  supplies air, the controlling valve  50  controls the exhaust port to close so as to make the secondary-stage cylinder  20  exhaust; moreover, the air pressure in the secondary-stage cylinder  20  is larger than the air pressure within the two primary-stage cylinders  10 ; the locking part  30  moves far away from the secondary-stage cylinder  20 ; the locking part  30  unlocks the sliding vane  22  of the secondary-stage cylinder  20 ; and the secondary-stage cylinder  20  is in a working state. In a heavy-load working condition, the two-stage operation mode of the compressor is opened, the air supply valve  42   a  is opened, the air supply part  42  performs an air supply operation, the control valve  50  is closed, and the exhaust port is closed. At this point, a low-pressure gas Ps entering the liquid dispenser  80  enters into the two primary-stage cylinders  10  for being suctioned and compressed; the middle-pressure gas Pm resulting from compression in the two primary-stage cylinders  10  and the air supply gas Pm are mixed within the enthalpy-increasing cavity  41  and then enter into the gas inlet port of the secondary-stage cylinder  20 ; at this point, a lower end of the locking part  30  is under a middle pressure Pm, while an upper end of the locking part  30  is under a high pressure Pd; the locking part  30  moves downward under the action of the gas pressure difference Pd-Pm; the sliding vane  22 , after being unlocked, operates; the secondary-stage cylinder  20  exhaust the compressed high-pressure gas through the inside of the housing of the compressor to the exhaust pipe and then into the air-conditioning system, thereby implementing a three-cylinder two-stage operation mode. 
         [0043]    As shown in  FIG. 5 , when the air supply part  42  is closed, the control valve  50  controls the exhaust port to open so as to make the enthalpy-increasing cavity  41  exhaust. The air pressure in the secondary-stage cylinder  20  is equal to the air pressure within the two primary-stage cylinders  10 . Under the resetting action force of the resetting element  60 , the locking part  30  moves towards the secondary-stage cylinder  20 ; the locking part  30  locks the sliding vane  22  of the secondary-stage cylinder  20 , and the secondary-stage cylinder  20  is in an offloaded state. In a low load condition, the two-cylinder single-stage operation mode of the compressor is opened. The air supply valve  42   a  is closed, and the control valve  50  is opened, and the exhaust port is opened. At this point, the low-pressure gas Ps entering from the liquid dispenser  80  enters into the two primary-stage cylinders  10  for being suctioned and compressed, respectively; an exhaust high pressure Pd resulting from compression in the two primary-stage cylinders  10  enters into the air inlet port of the secondary-stage cylinder  20  through the enthalpy-increasing cavity  41 . At this point, the lower end of the locking part  30  is under a high pressure Pd, the upper end of the locking part  30  is under high pressure Pd; the locking part  30  moves upward under the resetting action of the resetting element; the sliding vane  22  is locked; the secondary-stage cylinder  20  is offloaded to stop work; the high-pressure gas enters into the compressor housing from the enthalpy-increasing cavity  41  through the control valve  50 , and then exhausted into the air-conditioning system, thereby implementing a two-cylinder single-stage operation mode. 
         [0044]    The compressor in the present application can effectively solve the low energy-efficiency issue in the low load working condition, enhance its operating efficiency in the low load working condition, and also can implementing switching between the three-cylinder two-stage operation mode and the two-cylinder single-stage operation mode. 
         [0045]    What have been discussed above are only preferred embodiments of the present application, not for limiting the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement within the principle and spirit of the present application should be included within the protection scope of the present application.