Compressor oil level detection and protection device and refrigeration equipment

Abstract

The invention discloses a compressor oil level detection and protection device and refrigeration equipment. The compressor oil level detection and protection device comprises a main control chip and at least one oil level detection contact arranged on an oil storage part of a compressor, and each oil level detection contact is connected to the main control chip through an oil level detection circuit; the main control chip is further connected with at least one adjusting module used for adjusting the oil return state of the compressor, and the trigger state of the adjusting module is set according to the trigger state of the oil level detection circuit. Compared with the prior art, oil level detection is achieved in a hardware circuit mode, meanwhile, oil return control is added, and the system energy efficiency is improved.

Description

Technical Field

[0001] The invention relates to the field of refrigeration, in particular to a compressor oil level detection and protection device and a refrigeration device. Background Art

[0002] During the operation of the compressor, lubricating oil plays a vital role. Due to the operating characteristics of the air-conditioning unit, some lubricating oil will always be discharged from the compressor along with the refrigerant, and then return to the compressor through the condenser and evaporator. In the air-conditioning system, the evaporator pressure is low and the temperature is low, which leads to high viscosity of the lubricating oil and difficulty in oil return, which can easily lead to oil shortage in the compressor. Once oil shortage occurs, it will affect the lubrication of the compressor motor, causing wear and burning of the compressor.

[0003] Traditional compressor oil level control mostly uses test methods to determine periodic oil return. In patent CN105180533A, it only explains how to use the detection device to know the oil level, but does not clearly indicate how to achieve it. In addition, it is necessary to control the evaporation temperature, and the control logic is complex and difficult to achieve. If too much lubricating oil is retained in the evaporator, it will reduce the heat exchange efficiency of the evaporator, reduce the energy efficiency of the system, and increase the power consumption of the unit.

[0004] Therefore, how to design a compressor oil level detection and protection device and refrigeration equipment that can realize compressor oil level detection and combine with peripheral circuits to protect the compressor from wear due to lack of oil is a technical problem that needs to be solved urgently in the industry. Summary of the invention

[0005] In view of the problem in the prior art that the compressor lacks oil, which affects the lubrication of the compressor motor, causes wear and burns the compressor, the present invention proposes a compressor oil level detection and protection device and a refrigeration device.

[0006] The technical solution of the present invention is to propose a compressor oil level detection and protection device, comprising a main control chip and at least one oil level detection contact arranged in the oil storage part of the compressor, and each of the oil level detection contacts is connected to the main control chip through an oil level detection circuit;

[0007] The main control chip is also connected to at least one regulating module for regulating the oil return state of the compressor, and the triggering state of the regulating module is set according to the triggering state of the oil level detection circuit.

[0008] Furthermore, there are three regulating modules, namely a first regulating module for regulating the opening of the electronic expansion valve, a second regulating module for controlling the suction superheat, and a third regulating module for controlling the exhaust superheat.

[0009] Furthermore, the oil level detection contacts are provided with three, including a first oil level detection contact corresponding to the highest oil level, a second oil level detection contact corresponding to the middle of the oil level, and a third oil level detection contact corresponding to the lowest oil level;

[0010] When the oil level detection circuits corresponding to the three oil level detection contacts are all triggered, the first adjustment module, the second adjustment module, and the third adjustment module are not triggered;

[0011] When the oil level detection circuit corresponding to the second oil level detection contact and the oil level detection circuit corresponding to the third oil level detection contact are triggered, the first regulating module and the second regulating module are triggered;

[0012] When the oil level detection circuit corresponding to the third oil level detection contact is triggered, the first regulating module and the third regulating module are triggered;

[0013] When the oil level detection circuits corresponding to the three oil level detection contacts are not triggered, the main control chip reports a compressor failure, and the first regulating module, the second regulating module, and the third regulating module are not triggered.

[0014] Further, the oil level detection circuit includes a comparison circuit and a trigger circuit;

[0015] The input end of the comparison circuit is connected to the oil level detection contact, the output end of the comparison circuit is connected to the input end of the trigger circuit, and when the oil level in the oil storage part of the compressor reaches the oil level detection contact, the comparison circuit outputs a low level signal;

[0016] The input end of the trigger circuit is connected to the output end of the comparison circuit, the output end of the trigger circuit is connected to the main control chip, and when the input end of the trigger circuit receives a low level signal, the output end of the trigger circuit outputs a low level signal.

[0017] Further, the comparison circuit includes: a comparator U1A, a resistor R1, a resistor R2, a resistor R3, and a capacitor C1;

[0018] One end of the resistor R1 is grounded, the other end of the resistor R1 is connected to one end of the resistor R2, and the other end of the resistor R2 is connected to a power supply;

[0019] The non-inverting input terminal of the comparator U1A is connected between the resistor R1 and the resistor R2, the inverting input terminal of the comparator U1A is connected to one end of the resistor R3, the output terminal of the comparator U1A is connected to the input terminal of the trigger circuit as the output terminal of the comparison circuit, and the other end of the resistor R3 is connected to the oil level detection contact as the input terminal of the comparison circuit;

[0020] One end of the capacitor C1 is connected between the resistor R3 and the inverting input terminal of the comparator U1A, and the other end of the capacitor C1 is grounded.

[0021] Further, the trigger circuit includes: resistor R4, resistor R5, resistor R6, capacitor C2, capacitor C3, capacitor C4, PNP transistor Q1, 555 timer;

[0022] The emitter of the PNP transistor Q1 is connected to a power supply, the collector of the PNP transistor Q1 is connected to one end of the resistor R5, the base of the PNP transistor Q1 is connected to the output end of the comparison circuit as the input end of the trigger circuit, and the other end of the resistor R5 is grounded;

[0023] One end of the resistor R6 is connected to a power supply, the other end of the resistor R6 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is grounded;

[0024] The RESET pin of the 555 timer is connected to the power supply, the DISCH pin and the THRES pin of the 555 timer are connected between the resistor R6 and the capacitor C4, the TRIG pin of the 555 timer is connected to one end of the resistor R4, and the other end of the resistor R4 is connected between the collector of the PNP transistor Q1 and the resistor R5, the CONT pin of the 555 timer is connected to one end of the capacitor C3, and the other end of the capacitor C3 is grounded, and the OUT pin of the 555 timer is connected to the main control chip as the output end of the trigger circuit.

[0025] Furthermore, it also includes an inverting circuit connected between the trigger circuit and the main control chip, the input end of the inverting circuit is connected to the output end of the trigger circuit, the output end of the inverting circuit is connected to the main control chip, and when the input end of the inverting circuit receives a low level signal, the output end of the inverting circuit outputs a high level signal.

[0026] Furthermore, the inverting circuit includes: a resistor R7, a resistor R8, a resistor R9, a resistor R10, a capacitor C5, and an NPN transistor Q2;

[0027] Among them, one end of the resistor R8 is connected to the power supply, the other end of the resistor R8 is connected to one end of the resistor R10, the other end of the resistor R10 is connected to the main control chip as the output end of the inverting circuit, one end of the capacitor C5 is connected to the other end of the resistor R10, and the other end of the capacitor C5 is grounded;

[0028] The emitter of the NPN transistor Q2 is grounded, the collector of the NPN transistor Q2 is connected between the resistor R8 and the resistor R10, the base of the NPN transistor Q2 is connected to one end of the resistor R7, and the other end of the resistor R7 is connected to the output end of the trigger circuit as the input end of the inverter circuit;

[0029] One end of the resistor R9 is connected between the resistor R7 and the base of the NPN transistor Q2 , and the other end of the resistor R9 is grounded.

[0030] The invention also discloses a refrigeration device, which comprises the compressor oil level detection and protection device.

[0031] Furthermore, the refrigeration equipment is an air conditioner.

[0032] Compared with the prior art, the present invention has at least the following beneficial effects:

[0033] The present invention is provided with an oil level detection circuit and at least one adjustment module, which can detect the oil level inside the compressor through the oil level detection circuit, and at the same time, combined with the work of the adjustment module, change the oil return state of the compressor, and protect the compressor from wear due to lack of oil. At the same time, the trigger state of the adjustment module is set according to the trigger state of the oil level detection circuit, and the oil level detection circuit corresponds to the oil level detection contact. Therefore, the adjustment of the oil return state of the compressor by the adjustment module in the present invention is actually adjusted according to the current oil level, so that more reasonable control can be achieved, ensuring that the oil level is within a reasonable range under all working conditions, and improving the energy efficiency of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 It is the overall principle diagram of the operation of the compressor in the present invention;

[0036] Figure 2 This is the overall principle diagram of the compressor oil level detection and protection device in the present invention;

[0037] Figure 3 It is a circuit topology diagram of the oil level detection circuit in the present invention;

[0038] Figure 4 This is a flow chart of adjusting the oil return state of the compressor in the present invention. DETAILED DESCRIPTION

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] Thus, a feature indicated in this specification will be used to illustrate one of the features of an embodiment of the present invention, rather than implying that each embodiment of the present invention must have the described feature. In addition, it should be noted that this specification describes many features. Although some features can be combined together to illustrate possible system designs, these features can also be used in other combinations that are not explicitly described. Thus, unless otherwise stated, the described combinations are not intended to be limiting.

[0041] The principle and structure of the present invention are described in detail below with reference to the accompanying drawings and embodiments.

[0042] During the operation of the compressor, lubricating oil plays a vital role. Due to the operating characteristics of the air-conditioning unit, some lubricating oil will always be discharged from the compressor along with the refrigerant, and then return to the compressor through the condenser and evaporator. In the air-conditioning system, the evaporator pressure is low and the temperature is low, which leads to high viscosity of the lubricating oil and difficulty in oil return, which can easily lead to oil shortage in the compressor. Once oil shortage occurs, it will affect the lubrication of the compressor motor, causing wear and burning of the compressor.

[0043] Therefore, there is an urgent need to design a compressor oil level detection and protection device that can detect the oil level of the compressor and, when the compressor is short of oil, perform corresponding control to adjust the oil return state of the compressor to avoid wear of the compressor due to lack of oil.

[0044] Based on the above problems, the design idea of ​​the present invention is to propose a compressor oil level detection and protection device, which includes a main control chip and at least one oil level detection contact arranged in the oil storage part of the compressor, and each oil level detection contact is connected to the main control chip through an oil level detection circuit;

[0045] The main control chip is also connected to at least one regulating module for regulating the oil return state of the compressor, and the triggering state of the regulating module is set according to the triggering state of the oil level detection circuit.

[0046] From the above settings, it can be seen that the present invention has multiple oil level detection contacts, which are respectively arranged at different positions of the oil storage part of the compressor. When the oil level in the oil storage part of the compressor reaches the corresponding oil level detection contact, the oil level detection contact can detect the current oil level and provide a corresponding signal for the subsequent oil level detection circuit. That is, the present invention realizes the detection of the oil level in the oil storage part of the compressor by setting the oil level detection contact and the oil level detection circuit coordinated therewith;

[0047] At the same time, it can be seen from the above settings that at least one adjustment module is provided in the present invention, which is used to adjust the oil return state of the compressor, and its trigger state corresponds to the trigger state of the oil level detection circuit, that is, in the present invention, the oil level of the compressor is linked to the corresponding adjustment module, and can be adjusted according to the current oil level, so as to achieve more reasonable control.

[0048] Specifically, the present invention has three regulating modules, namely a first regulating module for regulating the opening of the electronic expansion valve, a second regulating module for controlling the suction superheat, and a third regulating module for controlling the exhaust superheat.

[0049] The oil return state of the compressor is mainly determined by the opening of the electronic expansion valve, the suction superheat, and the scheduling superheat. Therefore, after the first adjustment module, the second adjustment module, and the third adjustment module are set in the present invention, they can be used to adjust the oil return state of the compressor to solve the problem of oil shortage in the compressor.

[0050] Furthermore, in the present invention, three oil level detection contacts are also provided, including a first oil level detection contact corresponding to the highest oil level, a second oil level detection contact corresponding to the middle of the oil level, and a third oil level detection contact corresponding to the lowest oil level;

[0051] When the oil level detection circuits corresponding to the three oil level detection contacts are all triggered, the first regulating module, the second regulating module, and the third regulating module are not triggered;

[0052] When the oil level detection circuit corresponding to the second oil level detection contact and the oil level detection circuit corresponding to the third oil level detection contact are triggered, the first regulating module and the second regulating module are triggered;

[0053] When the oil level detection circuit corresponding to the third oil level detection contact is triggered, the first regulating module and the third regulating module are triggered;

[0054] When the oil level detection circuits corresponding to the three oil level detection contacts are not triggered, the main control chip reports a compressor failure, and the first regulating module, the second regulating module, and the third regulating module are not triggered.

[0055] It can be seen from the above settings that three oil level detection contacts are provided in the present invention, and the triggering state of the oil level detection circuit corresponding to the three oil level detection contacts corresponds to the triggering state of the adjustment module, that is, the oil level of the compressor is linked to the corresponding adjustment module in the present invention, and can be adjusted according to the current oil level, so as to achieve more reasonable control.

[0056] See also Figure 2, which is the overall principle diagram of the compressor oil level detection and protection device in the present invention, Figure 2 U1, U2, and U3 are the first oil level detection contact, the second oil level detection contact, and the third oil level detection contact, respectively. The left sides of the three oil level detection contacts are connected to an oil level detection circuit (in the present invention, the oil level detection contacts and the oil level detection circuits are in a one-to-one correspondence. For the sake of convenience, only one oil level detection circuit is used here).

[0057] From this attachment Figure 2 It can be seen that the first oil level detection contact is at the highest position. When the oil level in the compressor is higher than the first oil level detection contact, the oil level detection circuits corresponding to the three oil level detection contacts will be triggered simultaneously.

[0058] Similarly, when the oil level in the compressor is between the first oil level detection contact and the second oil level detection contact, the second oil level detection circuit and the third oil level detection circuit will be triggered simultaneously;

[0059] When the oil level in the compressor is between the second detection contact and the third oil level detection contact, only the third oil level detection circuit is triggered;

[0060] When the oil level in the compressor is lower than the third oil level detection contact, no oil level detection circuit will be triggered.

[0061] It can be well seen from the above working principle that the present invention can accurately obtain the current oil level information in the compressor based on the oil level detection circuit. At the same time, the oil level detection circuit is also connected to the main control chip, that is, the attached Figure 2 The MCU in the main control chip is connected to the first regulating module, the second regulating module, and the third regulating module on the left side;

[0062] Here the first adjustment module corresponds to the Figure 2 The electronic expansion valve control in the second regulating module corresponds to the attached Figure 2 Intake superheat control, the third regulation module corresponds to Figure 3 In the exhaust superheat control, after receiving the trigger information of the oil level detection circuit, the main control chip can adjust the working status of the three adjustment modules accordingly, and then adjust the oil return status of the compressor.

[0063] Through the above scheme, the present invention can link the oil level of the compressor with the corresponding adjustment module, and can adjust it according to the current oil level, so as to achieve more reasonable control.

[0064] Furthermore, the oil level detection circuit in the present invention is mainly divided into two parts, namely a comparison circuit and a trigger circuit;

[0065] The input end of the comparison circuit is connected to the oil level detection contact, the output end of the comparison circuit is connected to the input end of the trigger circuit, and when the oil level in the oil storage part of the compressor reaches the oil level detection contact, the comparison circuit outputs a low level signal;

[0066] The input end of the trigger circuit is connected to the output end of the comparison circuit, the output end of the trigger circuit is connected to the main control chip, and when the input end of the trigger circuit receives a low level signal, the output end of the trigger circuit outputs a low level signal.

[0067] For details, see Figure 3 , the comparison circuit in the present invention includes: a comparator U1A, a resistor R1, a resistor R2, a resistor R3, and a capacitor C1;

[0068] One end of the resistor R1 is grounded, the other end of the resistor R1 is connected to one end of the resistor R2, and the other end of the resistor R2 is connected to a power supply;

[0069] The non-inverting input terminal of the comparator U1A is connected between the resistor R1 and the resistor R2, the inverting input terminal of the comparator U1A is connected to one end of the resistor R3, the output terminal of the comparator U1A is connected to the input terminal of the trigger circuit as the output terminal of the comparison circuit, and the other end of the resistor R3 is connected to the oil level detection contact as the input terminal of the comparison circuit;

[0070] One end of the capacitor C1 is connected between the resistor R3 and the inverting input terminal of the comparator U1A, and the other end of the capacitor C1 is grounded.

[0071] The working principle of the oil level detection contact is that when the oil level in the compressor reaches the oil level contact, a high level signal is provided to the oil level detection circuit, otherwise a low level signal is provided;

[0072] like Figure 3 As shown, the oil level detection contact corresponding to U1 is a signal provided by the oil level detection circuit, which is input to the inverting input terminal of the comparator U1A through the resistor R4;

[0073] According to the working principle of the comparator U1A, when the level of the non-inverting input terminal of the comparator U1A is higher than the level of the inverting input terminal, the comparator U1A outputs a high-level signal. Conversely, when the level of the non-inverting input terminal of the comparator U1A is lower than the level of the inverting input terminal, the comparator U1A outputs a low-level signal.

[0074] Since the non-inverting input terminal of the comparator U1A is connected between the resistor R2 and the resistor R3, it can draw power from the power supply VDD and is at a high level. Therefore, when the inverting input terminal of the comparator U1A is at a high level, the comparator U1A outputs a low level signal, that is, when the oil level in the compressor reaches the corresponding oil level detection contact, the comparator U1A outputs a low level signal, otherwise it outputs a high level signal.

[0075] The above comparison circuit needs to work together with the trigger circuit to provide the main control chip with the corresponding signal to trigger the corresponding adjustment module. Figure 3 , the trigger circuit of the present invention includes: resistor R4, resistor R5, resistor R6, capacitor C2, capacitor C3, capacitor C4, PNP transistor Q1, 555 timer;

[0076] The emitter of the PNP transistor Q1 is connected to the power supply, the collector of the PNP transistor Q1 is connected to one end of the resistor R5, the base of the PNP transistor Q1 is connected to the output end of the comparison circuit as the input end of the trigger circuit, and the other end of the resistor R5 is grounded;

[0077] One end of the resistor R6 is connected to a power supply, the other end of the resistor R6 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is grounded;

[0078] The RESET pin of the 555 timer is connected to the power supply, the DISCH pin and THRES pin of the 555 timer are connected between the resistor R6 and the capacitor C4, the TRIG pin of the 555 timer is connected to one end of the resistor R4, the other end of the resistor R4 is connected between the collector of the PNP transistor Q1 and the resistor R5, the CONT pin of the 555 timer is connected to one end of the capacitor C3, the other end of the capacitor C3 is grounded, and the OUT pin of the 555 timer is connected to the main control chip as the output end of the trigger circuit.

[0079] Among them, the working principle of the 555 timer is that when the TRIG pin connected to it (corresponding to the input end of the trigger circuit in the previous article) receives a low-level signal, its corresponding OUT pin (corresponding to the output end of the trigger circuit in the previous article) will output a high-level signal, otherwise it will output a low-level signal.

[0080] For the PNP transistor Q1, its working principle is that when the level of the emitter is higher than the level of the base, the PNP transistor Q1 is turned on. Here, the emitter of the PNP transistor Q1 is connected to the power supply VDD at a high level, so when the base of the PNP transistor Q1 is at a low level, the PNP transistor Q1 can be turned on. Since the base of the PNP transistor Q1 is connected to the output end of the comparator U1A, according to the working principle of the comparison circuit in the previous article, the comparator U1A will only output a low-level signal when the oil level of the compressor reaches the corresponding oil level detection contact, that is, when the oil level of the compressor reaches the corresponding oil level detection contact, the PNP transistor Q1 is turned on, and at this time, the TRIG pin of the 555 timer is connected to the power supply VDD at a high level through the PNP transistor Q1, and at this time, the OUT pin of the 555 timer will output a low-level signal.

[0081] On the contrary, when the oil level of the compressor does not reach the corresponding oil level detection contact, the PNP transistor Q1 is cut off. At this time, the TRIG pin of the 555 timer is grounded to a low level through resistors R5 and R6. At this time, the OUT pin of the 555 timer will output a high level signal.

[0082] The combination of the above-mentioned comparison circuit and trigger circuit can realize all the functions of the oil level detection circuit. When the oil level of the compressor reaches the corresponding oil level detection contact, the oil level detection circuit will output a low-level signal, and the main control chip can determine the position of the oil level in the compressor based on the received signal.

[0083] If the oil level detection circuit corresponding to the first oil level detection contact outputs a high-level signal and the oil level detection circuits corresponding to the other two oil level detection contacts output low-level signals, it indicates that the oil level in the compressor is lower than the position of the first oil level detection contact and higher than the position of the second oil level detection contact. The oil level in the compressor can be accurately determined.

[0084] However, in practical applications, low-level signals are difficult to determine, and it may also be caused by circuit damage that makes it impossible to receive high-level signals. To avoid this situation, the present invention is also provided with an inverting circuit for inverting the low-level signal into a high-level signal, so that when the oil level of the compressor reaches the corresponding oil level detection contact, the oil level detection circuit will output a high-level signal.

[0085] Specifically, the oil level detection circuit in the present invention also includes an inverting circuit connected between the trigger circuit and the main control chip, the input end of the inverting circuit is connected to the output end of the trigger circuit, the output end of the inverting circuit is connected to the main control chip, and when the input end of the inverting circuit receives a low level signal, the output end of the inverting circuit outputs a high level signal.

[0086] For details, see Figure 3 , the inverting circuit includes: a resistor R7, a resistor R8, a resistor R9, a resistor R10, a capacitor C5, and an NPN transistor Q2;

[0087] Among them, one end of resistor R8 is connected to the power supply, the other end of resistor R8 is connected to one end of resistor R10, the other end of resistor R10 is connected to the main control chip as the output end of the inverting circuit, one end of capacitor C5 is connected to the other end of resistor R10, and the other end of capacitor C5 is grounded.

[0088] The emitter of the NPN transistor Q2 is grounded, the collector of the NPN transistor Q2 is connected between the resistor R8 and the resistor R10, the base of the NPN transistor Q2 is connected to one end of the resistor R7, and the other end of the resistor R7 is connected to the output end of the trigger circuit as the input end of the inverter circuit;

[0089] One end of the resistor R9 is connected between the resistor R7 and the base of the NPN transistor Q2, and the other end of the resistor R9 is grounded.

[0090] The working principle of the NPN transistor Q2 is that when its base voltage is higher than the emitter voltage, the NPN transistor Q2 is turned on, otherwise the NPN transistor Q2 is turned off. Since the emitter of the NPN transistor Q2 is grounded at a low level, the NPN transistor Q2 can be turned on only when the base of the NPN transistor Q2 (that is, the input end of the inverter circuit) is at a high level.

[0091] Combined with the working principle of the trigger circuit mentioned above, it can be known that when the oil level of the compressor reaches the corresponding oil level detection contact, the trigger circuit will output a low-level signal. At this time, the base and emitter of the NPN transistor Q2 are both low-level, and the NPN transistor Q2 is cut off. At this time, the output pin MCU-pin1 is connected to the power supply VDD through resistors R8 and R10, which is a high level;

[0092] On the contrary, when the oil level of the compressor does not reach the corresponding oil level detection contact, the trigger circuit will output a high-level signal. At this time, the NPN transistor Q2 is turned on. At this time, the current passing through the resistor R8 will directly pass through the NPN transistor Q2 to the ground (because the NPN transistor Q2 is equivalent to a wire when it is turned on). At this time, no current passes through the resistor R10, and the output pin MCU-pin1 is at a low level.

[0093] Based on the above-mentioned inverting circuit, the working logic of the oil level detection circuit in the present invention becomes: when the oil level in the compressor reaches the oil level corresponding to the oil level detection contact, the oil level detection circuit outputs a high level signal, otherwise it outputs a low level signal.

[0094] The main control chip can determine the oil level in the compressor only based on the received high-level signal.

[0095] Based on the above settings, the principle of oil return state adjustment in the present invention is:

[0096] When the oil level detection circuits corresponding to the three oil level detection contacts are all triggered, the first regulating module, the second regulating module, and the third regulating module are not triggered;

[0097] When the oil level detection circuit corresponding to the second oil level detection contact and the oil level detection circuit corresponding to the third oil level detection contact are triggered, the first regulating module and the second regulating module are triggered;

[0098] When the oil level detection circuit corresponding to the third oil level detection contact is triggered, the first regulating module and the third regulating module are triggered;

[0099] When the oil level detection circuits corresponding to the three oil level detection contacts are not triggered, the main control chip reports a compressor failure, and the first regulating module, the second regulating module, and the third regulating module are not triggered.

[0100] Here, the oil level detection circuit is triggered to indicate a high level output, and is not triggered to indicate a low level output. The first adjustment module corresponds to Figure 2 In the electronic expansion valve control, the first regulating module triggers, that is, regulates the opening of the electronic expansion valve;

[0101] The second adjustment module corresponds to Figure 2 Intake air superheat control, the second regulating module is triggered, i.e., regulates the intake air superheat;

[0102] The third adjustment module corresponds to Figure 2 In the exhaust gas superheat control, the third regulating module triggers, that is, regulates, the exhaust gas superheat.

[0103] See also Figure 4 The specific process of adjusting the oil return state in the present invention is as follows:

[0104] First, the oil level is detected, which is realized by the oil level detection circuit, and then it is determined whether the oil level in the compressor is less than H1. Here, the oil level H1 corresponds to the position of the first oil level detection contact. If it is higher than the oil level H1, it indicates that the compressor does not have an oil shortage problem, and then it returns to the detection again. If it is less than the oil level H1, the first regulating module and the second regulating module are controlled to be triggered to increase the electronic expansion valve and increase the suction superheat, thereby accelerating the oil return speed;

[0105] If it is less than the oil level H2, where the oil level H2 corresponds to the position of the second oil level detection contact, the first regulating module and the third regulating module are controlled to be triggered to reduce the electronic expansion valve, and at the same time increase the exhaust temperature of the compressor, increase the exhaust superheat of the compressor, so that the lubricating oil in the compressor can quickly recover the superheat, reduce the dissolution rate of the lubricating oil in the refrigerant, and restore the oil level to normal;

[0106] If it is less than the oil level H3, where the oil level H3 corresponds to the position of the third oil level detection contact, which is the lowest oil level in the compressor. If it is lower than the oil level H3, it indicates that the compressor is short of oil and a fault alarm is required.

[0107] See also Figure 1 , which is an overall principle diagram of the operation of the compressor in the present invention, wherein U1, U2, and U3 correspond to different oil level detection contacts, and the compressor forms a circuit through an indoor heat exchanger, an outdoor heat exchanger, and an expansion valve.

[0108] Furthermore, the present invention also proposes a refrigeration device, which has the above compressor oil level detection and protection device.

[0109] Furthermore, the above-mentioned refrigeration equipment is an air conditioner.

[0110] In summary, compared with the prior art, the present invention has at least the following beneficial effects:

[0111] The present invention is provided with an oil level detection circuit and at least one adjustment module, which can detect the oil level inside the compressor through the oil level detection circuit, and at the same time, combined with the work of the adjustment module, change the oil return state of the compressor, and protect the compressor from wear due to lack of oil. At the same time, the trigger state of the adjustment module is set according to the trigger state of the oil level detection circuit, and the oil level detection circuit corresponds to the oil level detection contact. Therefore, the adjustment of the oil return state of the compressor by the adjustment module in the present invention is actually adjusted according to the current oil level, so that more reasonable control can be achieved, ensuring that the oil level is within a reasonable range under all working conditions, and improving the energy efficiency of the system.

[0112] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A compressor oil level detection and protection device, characterized in that: It includes a main control chip and at least one oil level detection contact point arranged in the oil storage part of the compressor, and each of the oil level detection contacts is connected to the main control chip through an oil level detection circuit; The main control chip is also connected to at least one regulating module for regulating the oil return state of the compressor, and the triggering state of the regulating module is set according to the triggering state of the oil level detection circuit.

2. The compressor oil level detection and protection device according to claim 1, characterized in that: The regulating modules are provided with three, namely a first regulating module for regulating the opening of the electronic expansion valve, a second regulating module for controlling the suction superheat, and a third regulating module for controlling the exhaust superheat.

3. The compressor oil level detection and protection device according to claim 2, characterized in that: The oil level detection contacts are provided with three, including a first oil level detection contact corresponding to the highest oil level, a second oil level detection contact corresponding to the middle of the oil level, and a third oil level detection contact corresponding to the lowest oil level; When the oil level detection circuits corresponding to the three oil level detection contacts are all triggered, the first adjustment module, the second adjustment module, and the third adjustment module are not triggered; When the oil level detection circuit corresponding to the second oil level detection contact and the oil level detection circuit corresponding to the third oil level detection contact are triggered, the first regulating module and the second regulating module are triggered; When the oil level detection circuit corresponding to the third oil level detection contact is triggered, the first regulating module and the third regulating module are triggered; When the oil level detection circuits corresponding to the three oil level detection contacts are not triggered, the main control chip reports a compressor failure, and the first regulating module, the second regulating module, and the third regulating module are not triggered.

4. The compressor oil level detection and protection device according to claim 1, characterized in that: The oil level detection circuit includes a comparison circuit and a trigger circuit; The input end of the comparison circuit is connected to the oil level detection contact, the output end of the comparison circuit is connected to the input end of the trigger circuit, and when the oil level in the oil storage part of the compressor reaches the oil level detection contact, the comparison circuit outputs a low level signal; The input end of the trigger circuit is connected to the output end of the comparison circuit, the output end of the trigger circuit is connected to the main control chip, and when the input end of the trigger circuit receives a low level signal, the output end of the trigger circuit outputs a low level signal.

5. The compressor oil level detection and protection device according to claim 4, characterized in that: The comparison circuit includes: a comparator U1A, a resistor R1, a resistor R2, a resistor R3, and a capacitor C1; One end of the resistor R1 is grounded, the other end of the resistor R1 is connected to one end of the resistor R2, and the other end of the resistor R2 is connected to a power supply; The non-inverting input terminal of the comparator U1A is connected between the resistor R1 and the resistor R2, the inverting input terminal of the comparator U1A is connected to one end of the resistor R3, the output terminal of the comparator U1A is connected to the input terminal of the trigger circuit as the output terminal of the comparison circuit, and the other end of the resistor R3 is connected to the oil level detection contact as the input terminal of the comparison circuit; One end of the capacitor C1 is connected between the resistor R3 and the inverting input terminal of the comparator U1A, and the other end of the capacitor C1 is grounded.

6. The compressor oil level detection and protection device according to claim 4, characterized in that: The trigger circuit includes: a resistor R4, a resistor R5, a resistor R6, a capacitor C2, a capacitor C3, a capacitor C4, a PNP transistor Q1, and a 555 timer; The emitter of the PNP transistor Q1 is connected to a power supply, the collector of the PNP transistor Q1 is connected to one end of the resistor R5, the base of the PNP transistor Q1 is connected to the output end of the comparison circuit as the input end of the trigger circuit, and the other end of the resistor R5 is grounded; One end of the resistor R6 is connected to a power supply, the other end of the resistor R6 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is grounded; The RESET pin of the 555 timer is connected to the power supply, the DISCH pin and the THRES pin of the 555 timer are connected between the resistor R6 and the capacitor C4, the TRIG pin of the 555 timer is connected to one end of the resistor R4, and the other end of the resistor R4 is connected between the collector of the PNP transistor Q1 and the resistor R5, the CONT pin of the 555 timer is connected to one end of the capacitor C3, and the other end of the capacitor C3 is grounded, and the OUT pin of the 555 timer is connected to the main control chip as the output end of the trigger circuit.

7. The compressor oil level detection and protection device according to claim 4, characterized in that: It also includes an inverting circuit connected between the trigger circuit and the main control chip, the input end of the inverting circuit is connected to the output end of the trigger circuit, the output end of the inverting circuit is connected to the main control chip, and when the input end of the inverting circuit receives a low level signal, the output end of the inverting circuit outputs a high level signal.

8. The compressor oil level detection and protection device according to claim 7, characterized in that: The inverting circuit includes: a resistor R7, a resistor R8, a resistor R9, a resistor R10, a capacitor C5, and an NPN transistor Q2; Among them, one end of the resistor R8 is connected to the power supply, the other end of the resistor R8 is connected to one end of the resistor R10, the other end of the resistor R10 is connected to the main control chip as the output end of the inverting circuit, one end of the capacitor C5 is connected to the other end of the resistor R10, and the other end of the capacitor C5 is grounded; The emitter of the NPN transistor Q2 is grounded, the collector of the NPN transistor Q2 is connected between the resistor R8 and the resistor R10, the base of the NPN transistor Q2 is connected to one end of the resistor R7, and the other end of the resistor R7 is connected to the output end of the trigger circuit as the input end of the inverter circuit; One end of the resistor R9 is connected between the resistor R7 and the base of the NPN transistor Q2 , and the other end of the resistor R9 is grounded.

9. A refrigeration device, characterized in that: The refrigeration equipment has a compressor oil level detection and protection device as described in any one of claims 1 to 8.

10. The refrigeration device according to claim 9, characterized in that: The refrigeration equipment is an air conditioner.

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