Sensor

Abstract

The present disclosure relates to a sensor. The sensor according to an embodiment of the present disclosure may comprise: a cap; electrodes facing the cap and spaced apart from each other; and pins passing through the cap and electrically connected to the electrodes, wherein the electrodes may comprise: an upper electrode shaped like a horizontal plate; a lower electrode positioned below the upper electrode; and a shield electrode disposed between the upper electrode and the lower electrode.

Description

sensor

[0001] The present disclosure relates to a sensor, and more particularly, to a sensor that detects oil present inside a compressor.

[0002] Compressors are installed in home appliances such as refrigerators and air conditioners, as well as in vehicles, to compress refrigerant. Connected to a condenser and an evaporator, the compressor compresses the refrigerant vaporized in the evaporator and supplies it to the condenser.

[0003] To protect the compressor from mechanical friction, lubrication and cooling are provided by oil, and the compressor must always maintain a certain level of oil. The oil within the compressor circulates through the refrigerant cycle along with the refrigerant discharged from the compressor. If oil accumulates in the condenser, evaporator, and piping of the refrigerant cycle, it can lead to a decline in the system's performance. Furthermore, if oil recovery is not smooth, the amount of oil within the compressor can be insufficient, potentially causing compressor damage. To prevent such compressor damage, the system performs an oil recovery operation to recover oil accumulated in the condenser, evaporator, and piping back to the compressor.

[0004] Conventionally, a separate oil level sensor is installed in the compressor, and oil recovery operation is performed based on the amount of oil detected by the oil level sensor. Using an oil level sensor reduces unnecessary oil recovery operations, thereby improving energy efficiency and compressor performance reliability.

[0005] However, according to the conventional method, the oil level sensor is placed at a predetermined location inside the compressor, and it is only possible to check whether the amount of oil present inside the compressor corresponds to the predetermined location where the oil level sensor is installed. Therefore, there is a problem that multiple oil level sensors must be installed at various locations inside the compressor to accurately detect the amount of oil present inside the compressor.

[0006] The present disclosure aims to solve the above-mentioned and other problems.

[0007] Another purpose is to provide a sensor that can accurately detect the concentration of oil present inside the compressor.

[0008] Another object is to provide a sensor capable of accurately detecting the height of the oil surface based on the concentration of oil present inside the compressor.

[0009] Another purpose is to provide a sensor that can accurately detect the amount of oil present inside the compressor.

[0010] Another objective is to provide a sensor optimized to detect oil concentration, oil surface height, and oil quantity simultaneously using multiple electrodes.

[0011] Another purpose is to provide a sensor whose detection range for the height of the oil surface is not limited by the size of the electrode, using the self-capacitance method.

[0012] Another purpose is to provide various examples of sensing modules of the sensor.

[0013] In order to achieve the above or other purposes, a sensor according to one embodiment of the present disclosure may include: a cap; electrodes facing the cap and spaced apart from each other; and pins penetrating the cap and electrically connected to the electrodes, wherein the electrodes may include: an upper electrode in the shape of a horizontal plate; a lower electrode positioned below the upper electrode; and a shield electrode disposed between the upper electrode and the lower electrode.

[0014] The effects of the sensor according to the present disclosure are described as follows.

[0015] According to at least one embodiment of the present disclosure, the concentration of oil present inside a compressor can be accurately detected.

[0016] According to at least one embodiment of the present disclosure, the height of the oil surface can be accurately detected based on the concentration of oil present inside the compressor.

[0017] According to at least one embodiment of the present disclosure, the amount of oil present inside a compressor can be accurately detected.

[0018] According to at least one embodiment of the present disclosure, a sensor optimized to detect oil concentration, oil surface height, and oil amount together using a plurality of electrodes can be provided.

[0019] According to at least one embodiment of the present disclosure, by using a self-capacitance method, the detection range for the height of the oil surface may not be limited by the size of the electrode.

[0020] According to at least one embodiment of the present disclosure, various examples of a sensing module of a sensor can be provided.

[0021] Further scope of the applicability of the present disclosure will become apparent from the detailed description below. However, since various modifications and variations within the spirit and scope of the present disclosure will become apparent to those skilled in the art, it should be understood that the detailed description and specific examples, such as preferred embodiments of the present disclosure, are given by way of example only.

[0022] FIG. 1A and FIG. 1B are diagrams illustrating the configuration of a system according to one embodiment of the present disclosure.

[0023] FIG. 2 is a block diagram of a system according to one embodiment of the present disclosure.

[0024] FIG. 3 is a block diagram of a sensor according to one embodiment of the present disclosure.

[0025] FIGS. 4A to 6B are drawings illustrating the configuration of an electrode assembly according to embodiments of the present disclosure.

[0026] FIGS. 7 to 9 are drawings for reference in the description of a sensor according to one embodiment of the present disclosure.

[0027] FIGS. 10 to 17 are drawings illustrating the configuration of an electrode assembly according to embodiments of the present disclosure.

[0028] FIGS. 18 to 23 are drawings illustrating a sensing module of a sensor according to one embodiment of the present disclosure.

[0029] FIGS. 24 to 27 are drawings illustrating a sensing module of a sensor according to one embodiment of the present disclosure.

[0030] FIGS. 28 to 31 are drawings illustrating a sensing module of a sensor according to an embodiment of the present disclosure.

[0031] Hereinafter, the present disclosure will be described in detail with reference to the drawings. In the drawings, portions irrelevant to the description are omitted to clearly and concisely describe the present disclosure, and the same reference numerals are used for identical or extremely similar portions throughout the specification.

[0032] The suffixes "module" and "part" used in the following description are given solely for the convenience of writing this specification and do not impart any particularly significant meaning or role to the components themselves. Therefore, the terms "module" and "part" may be used interchangeably.

[0033] In this application, it should be understood that terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0034] Additionally, while terms such as "first" and "second" may be used in this specification to describe various elements, these elements are not limited by these terms. These terms are used only to distinguish one element from another.

[0035] Hereinafter, directions are defined based on the rectangular coordinate system. In the rectangular coordinate system, the x-axis direction can be defined as the left-right direction. At this time, the direction toward +x with respect to the origin can mean the right direction, and the direction toward -x can mean the left direction. In addition, the y-axis direction can be defined as the front-back direction. At this time, the direction toward +y with respect to the origin can mean the front direction, and the direction toward -y can mean the rear direction. In addition, the z-axis direction can be defined as the up-down direction. At this time, the direction toward +z with respect to the origin can mean the upward direction, and the direction toward -z can mean the downward direction.

[0036] FIG. 1A and FIG. 1B are diagrams illustrating a system according to various embodiments of the present invention.

[0037] Referring to FIGS. 1A and 1B, the system may include a compressor (1) that compresses a refrigerant. The refrigerant compressed by the compressor (1) may circulate through a refrigerant cycle. In the present disclosure, the system is described as an air conditioner that provides heat-exchanged air to a room based on a refrigerant cycle.

[0038] The system may include an outdoor unit (ODU) and an indoor unit (IDU) connected to each other by refrigerant piping. The system may further include a remote control unit (RCU). The outdoor unit (ODU), indoor unit (IDU), and / or remote control unit (RCU) may transmit and receive signals to and from each other.

[0039] The outdoor unit (ODU) may be equipped with a compressor (1), an oil separator (2), a changeover valve (3), an outdoor heat exchanger (4), an outdoor expansion valve (E2), and / or an accumulator (6). The indoor unit (IDU) may be equipped with an indoor heat exchanger (5) and an indoor expansion valve (E1).

[0040] The compressor (1) can compress the refrigerant introduced from the accumulator (6) to high temperature and high pressure. For example, the compressor (1) may be an inverter compressor capable of controlling the amount of refrigerant and the discharge pressure of the refrigerant by adjusting the operating frequency. For example, the compressor (1) may be an oil compressor that uses oil as a lubricant.

[0041] The oil separator (2) can recover oil from the refrigerant discharged from the compressor (1) and supply it back to the compressor (1). At this time, the first check valve (C1) can be installed in the pipe through which the oil separated from the oil separator (2) flows, thereby limiting the flow direction of the oil to the direction from the oil separator (2) to the compressor (1).

[0042] The switching valve (3) can selectively guide the refrigerant flowing from the oil separator (2) to the outdoor heat exchanger (4) or the indoor heat exchanger (5). For example, the switching valve (3) may be a four-way valve. In this case, the second check valve (C2) can limit the flow direction of the refrigerant to the direction from the oil separator (2) to the switching valve (3).

[0043] The outdoor heat exchanger (4) can exchange heat between the refrigerant and outdoor air. The direction of heat transfer between the refrigerant and outdoor air in the outdoor heat exchanger (4) may vary depending on the system's operating mode, i.e., heating operation or cooling operation. An outdoor fan (not shown) is installed on one side of the outdoor heat exchanger (4) to control the amount of air supplied to the outdoor heat exchanger (4).

[0044] The indoor heat exchanger (5) can exchange heat between the refrigerant and indoor air. The direction of heat transfer between the refrigerant and indoor air in the indoor heat exchanger (5) may vary depending on the system's operating mode, i.e., heating operation or cooling operation. An indoor fan (not symbolized) is installed on one side of the indoor heat exchanger (5) to control the amount of air supplied to the indoor heat exchanger (5).

[0045] For example, the indoor heat exchanger (5) may include a plurality of indoor heat exchangers (5a, 5b, 5c). In this case, the indoor unit (IDU) may include a first indoor unit (IDUa) having a first indoor heat exchanger (5a), a first indoor fan, and a first indoor expansion valve (E1a), a second indoor unit (IDUb) having a second indoor heat exchanger (5b), a second indoor fan, and a second indoor expansion valve (E1b), and a third indoor unit (IDUc) having a third indoor heat exchanger (5c), a third indoor fan, and a third indoor expansion valve (E1c). Meanwhile, in response to the indoor cooling or heating demand load, some of the plurality of indoor heat exchangers (5a, 5b, 5c) may be operated, and the rest may not be operated.

[0046] Expansion valves (E1, E2) are installed between the outdoor heat exchanger (4) and the indoor heat exchanger (5), and can expand refrigerant that has passed through the outdoor heat exchanger (4) or the indoor heat exchanger (5). In addition, the expansion valves (E1, E2) may include an outdoor expansion valve (E2) adjacent to the outdoor heat exchanger (4) and an indoor expansion valve (E1) adjacent to the indoor heat exchanger (5). In this case, the outdoor expansion valve (E2) may be used to expand refrigerant that has passed through the indoor heat exchanger (5), and the indoor expansion valve (E1) may be used to expand refrigerant that has passed through the outdoor heat exchanger (4). For example, the expansion valves (E1, E2) may be EEVs (Electronic Expansion Valves) capable of controlling the opening of a flow path of a refrigerant pipe in which the expansion valves (E1, E2) are installed.

[0047] For example, the indoor expansion valve (E1) may include a first indoor expansion valve (E1a) that expands refrigerant provided to the first indoor heat exchanger (5a), a second indoor expansion valve (E1b) that expands refrigerant provided to the second indoor heat exchanger (5b), and a third indoor expansion valve (E1c) that expands refrigerant provided to the third indoor heat exchanger (5c).

[0048] A plurality of sensors (not shown) can measure the temperature and / or pressure of the refrigerant flowing through the refrigerant pipe.

[0049] A control unit (not shown) is electrically connected to each component of the system and can control the operation of each component of the system.

[0050] Referring to Fig. 1a, when a heating operation signal is input to the system, the control unit can perform heating operation of the system. For example, the heating operation signal may be a signal arbitrarily input by the user. As another example, the heating operation signal may be a signal provided to the control unit by a thermostat installed in an indoor space when the indoor temperature detected by the indoor temperature sensor is lower than a desired temperature set by the user by a certain level.

[0051] Specifically, the low-temperature, low-pressure refrigerant flowing into the compressor (1) from the accumulator (6) can be compressed to high-temperature, high-pressure refrigerant in the compressor (1) and discharged to the oil separator (2). Then, the refrigerant from which oil has been separated in the oil separator (2) can flow into the second indoor heat exchanger (5b) through the switching valve (3) and the first service valve (SV1). At this time, the second indoor expansion valve (E1b) can completely open the refrigerant flow path that passes through the second indoor heat exchanger (5b) and leads to the outdoor heat exchanger (4). Then, the first indoor expansion valve (E1a) and the third indoor expansion valve (E1c) can close the refrigerant flow path that passes through the first indoor heat exchanger (5a) and the third indoor heat exchanger (5c) and leads to the outdoor heat exchanger (4). Additionally, when the required heating load increases, the first indoor expansion valve (E1a) and / or the third indoor expansion valve (E1c) may also be opened.

[0052] As heat energy is transferred from the refrigerant to the indoor air in the second indoor heat exchanger (5b), the refrigerant can be condensed. At this time, the second indoor heat exchanger (5b) can function as a condenser. And, according to the heat exchange between the refrigerant and the indoor air, the indoor space can be heated. The refrigerant condensed while passing through the second indoor heat exchanger (5b) can pass through the second indoor expansion valve (E1b) and the second service valve (SV2) and then the outdoor expansion valve (E2). The refrigerant expanded while passing through the outdoor expansion valve (E2) can be distributed to multiple points of the outdoor heat exchanger (4) through the distributor (41).

[0053] As the heat energy of the outdoor air is transferred to the refrigerant in the outdoor heat exchanger (4), the refrigerant can evaporate. At this time, the outdoor heat exchanger (4) can function as an evaporator. The refrigerant that has evaporated while passing through the outdoor heat exchanger (4) can be sequentially introduced into the compressor (1) through the header (42), the switching valve (3), and the accumulator (6). Thus, the refrigerant cycle for the heating operation of the aforementioned system can be completed.

[0054] Referring to Fig. 1b, when a cooling operation signal is input to the system, the control unit can perform cooling operation of the system. For example, the cooling operation signal may be a signal arbitrarily input by the user. As another example, the cooling operation signal may be a signal provided to the control unit by a thermostat installed in an indoor space when the indoor temperature detected by the indoor temperature sensor is higher than a desired temperature set by the user by a certain level.

[0055] Specifically, the low-temperature, low-pressure refrigerant flowing into the compressor (1) from the accumulator (6) can be compressed to high temperature, high pressure in the compressor (1) and discharged to the oil separator (2). Then, the refrigerant from which oil has been separated in the oil separator (2) can flow into the outdoor heat exchanger (4) through the switching valve (3) and the header (42).

[0056] As heat energy is transferred from the refrigerant to the outdoor air in the outdoor heat exchanger (4), the refrigerant can be condensed. At this time, the outdoor heat exchanger (4) can function as a condenser.

[0057] The refrigerant condensed while passing through the outdoor heat exchanger (4) can sequentially flow into the second indoor expansion valve (E1b) through the distributor (41), the outdoor expansion valve (E2), and the second service valve (SV2). At this time, the outdoor expansion valve (E2) can fully open the flow path. Then, the refrigerant expanded while passing through the second indoor expansion valve (E1b) can flow into the second indoor heat exchanger (5b). In addition, when the required cooling load increases, the first indoor expansion valve (E1a) and / or the third indoor expansion valve (E1c) can also be opened to a certain degree.

[0058] As the heat energy of indoor air is transferred to the refrigerant in the second indoor heat exchanger (5b), the refrigerant can evaporate. At this time, the second indoor heat exchanger (5b) can function as an evaporator. And, according to the heat exchange between the refrigerant and the indoor air, the indoor space can be cooled. The refrigerant that has evaporated while passing through the second indoor heat exchanger (5b) can sequentially pass through the first service valve (SV1), the changeover valve (3), and the accumulator (6) and then flow into the compressor (1). Thus, the refrigerant cycle for the cooling operation of the aforementioned system can be completed.

[0059] Meanwhile, the system can perform an oil recovery operation. For example, when performing an oil recovery operation, the system can control the switching valve (3) so that the refrigerant discharged from the compressor (1) flows to the outdoor heat exchanger (4). At this time, the refrigerant can be condensed by heat exchange between the refrigerant and the outdoor air occurring in the outdoor heat exchanger (4). The refrigerant condensed in the outdoor heat exchanger (4) can be introduced into the indoor unit (IDU). The refrigerant can be evaporated by heat exchange between the refrigerant introduced into the indoor unit (IDU) and the indoor air.

[0060] According to one embodiment, the system may increase the operating frequency of the compressor (1) above a certain level when performing an oil recovery operation. For example, the system may set the operating frequency of the compressor (1) to the maximum when performing an oil recovery operation. The system may stop the operation of the indoor fan when performing an oil recovery operation. The system may control the operation of the outdoor fan based on the pressure of the outdoor unit-side pipe when performing an oil recovery operation. For example, when the pressure of the outdoor unit-side pipe exceeds a predetermined standard, the outdoor fan may be operated, and when the pressure is below the predetermined standard, the operation of the outdoor fan may be stopped.

[0061] FIG. 2 is a block diagram of a system according to one embodiment of the present disclosure.

[0062] Referring to FIG. 2, the system may include a communication unit (210), a sensor unit (220), a memory (230), a fan drive unit (240) that drives a fan (241), a compressor drive unit (250) that drives a compressor (251, compressor (1) of FIG. 1A), and / or a control unit (260).

[0063] The communication unit (210) may include at least one communication module. For example, the communication unit (210) may be provided in each of the outdoor unit (ODU) and the indoor unit (IDU), and the outdoor unit (ODU) and the indoor unit (IDU) may transmit and receive data between each other. For example, the communication unit (210) may be provided in a remote control unit (RCU).

[0064] The communication method of the outdoor unit (ODU), indoor unit (IDU) and / or remote control unit (RCU) may be, for example, a communication method using a power line, a serial communication method (e.g., RS-485 communication), a wired communication method through a refrigerant pipe, or a wireless communication method such as Wi-fi, Bluetooth, Beacon, or Zigbee.

[0065] The communication unit (210) can transmit and receive data with external devices. For example, the communication unit (210) can connect to a server connected to an external network and transmit and receive data.

[0066] The sensor unit (220) may be equipped with at least one sensor and may transmit data on a detection value detected through the sensor to the control unit (260).

[0067] The sensor unit (220) may be equipped with a heat exchanger temperature sensor (not shown). For example, the heat exchanger temperature sensor may be placed inside the indoor heat exchanger (5) and detect the temperature of the indoor heat exchanger (5).

[0068] The sensor unit (220) may be equipped with a pipe temperature sensor (not shown). The pipe temperature sensor can detect the temperature of the refrigerant flowing through each pipe of the system. For example, the pipe temperature sensor may be disposed on an inlet pipe of the indoor unit (IDU) and / or an outlet pipe of the indoor unit (IDU) to detect the temperature of the refrigerant flowing through the pipe. For example, the pipe temperature sensor may be disposed on a pipe connected to the compressor (251) to detect the temperature of the refrigerant flowing into the compressor (251) (hereinafter, referred to as suction temperature) and / or the temperature of the refrigerant discharged from the compressor (251) (hereinafter, referred to as discharge temperature).

[0069] The sensor unit (210) may be equipped with a pressure sensor (not shown). The pressure sensor (not shown) can detect the pressure of the gaseous refrigerant flowing through each pipe of the system. For example, the pressure sensor may be placed in a pipe connected to the compressor (251) and detect the pressure of the refrigerant flowing into the compressor (251) (hereinafter, suction pressure) and / or the pressure of the refrigerant discharged from the compressor (251) (hereinafter, discharge pressure).

[0070] The sensor unit (220) may be equipped with an indoor temperature sensor (not shown) that detects indoor temperature and / or an outdoor temperature sensor (not shown) that detects outdoor temperature.

[0071] The sensor unit (220) may be equipped with an indoor humidity sensor (not shown) that detects indoor humidity and / or an outdoor humidity sensor (not shown) that detects outdoor humidity.

[0072] The sensor unit (220) may include a sensor (300, see FIG. 3) (hereinafter, “oil sensor”) that outputs a signal corresponding to oil stored inside the compressor (251). The oil sensor (300) may detect the height of the surface of the fluid stored inside the compressor (251). The oil sensor (300) may detect the amount of the fluid stored inside the compressor (251). The oil sensor (300) may detect the concentration of oil in the fluid. The fluid stored inside the compressor (251) may include at least oil. The fluid stored inside the compressor (251) may further include a refrigerant.

[0073] The memory (230) can store data related to the operation of each component provided in the system.

[0074] The memory (230) can store programs for signal processing and control within the control unit (260), and can store processed data and data to be processed. For example, the memory (230) can store application programs designed for the purpose of performing various tasks that can be processed by the control unit (260), and can selectively provide some of the stored application programs upon request from the control unit (260).

[0075] The memory (230) may include, for example, at least one of volatile memory (e.g., DRAM, SRAM, SDRAM, etc.) or non-volatile memory (e.g., flash memory, hard disk drive (HDD), solid-state drive (SSD), etc.).

[0076] The fan drive unit (240) can drive a fan (241) provided in the system. For example, the fan (241) may include an outdoor fan and / or an indoor fan.

[0077] The fan driving unit (240) may include a rectifier (not shown) that rectifies AC power into DC power and outputs it, a dc capacitor (not shown) that stores a pulsating voltage from the rectifier, an inverter (not shown) that has a plurality of switching elements and converts and outputs smoothed DC power into three-phase AC power of a predetermined frequency, and / or at least one motor that drives a fan (241) according to three-phase AC power output from the inverter.

[0078] Meanwhile, the fan drive unit (240) may be provided with separate configurations for driving the outdoor fan and the indoor fan. For example, the system may include a first fan drive unit for driving the outdoor fan and a second fan drive unit for driving the indoor fan.

[0079] The compressor driving unit (250) can drive the compressor (251). The compressor driving unit (250) may include a rectifier (not shown) that rectifies AC power into DC power and outputs it, a dc capacitor (not shown) that stores a pulsating voltage from the rectifier, an inverter (not shown) that has a plurality of switching elements and converts and outputs smoothed DC power into three-phase AC power of a predetermined frequency, and / or a compressor motor (102b) that drives the compressor (251) according to the three-phase AC power output from the inverter.

[0080] The control unit (260) can control the overall operation of the system. The control unit (260) can be connected to each component provided in the system, and can control the overall operation of each component by transmitting and / or receiving signals between each component.

[0081] The control unit (260) can control the operation of the fan drive unit (240) to change the rotation speed of the fan (241). For example, the fan drive unit (240) can change the rotation speed of the outdoor fan by changing the frequency of the three-phase AC power output to the outdoor fan motor according to the control of the control unit (260). For example, the fan drive unit (240) can change the rotation speed of the indoor fan by changing the frequency of the three-phase AC power output to the indoor fan motor according to the control of the control unit (260).

[0082] The control unit (260) can change the operating frequency of the compressor (251) by controlling the operation of the compressor drive unit (250). For example, the compressor drive unit (250) can change the operating frequency of the compressor (251) by changing the frequency of the three-phase AC power output to the compressor motor (102b) according to the control of the control unit (260).

[0083] The control unit (260) may be provided not only in the outdoor unit (ODU), but also in the indoor unit (IDU), the outdoor unit (ODU), and / or the remote control unit (RCU).

[0084] The control unit (260) may include at least one processor, and may control the overall operation of the system using the processor included therein. Here, the processor may be a general processor, such as a central processing unit (CPU). Of course, the processor may also be a dedicated device, such as an ASIC, or another hardware-based processor.

[0085] The control unit (260) can acquire data related to each component provided in the system. At this time, the control unit (260) can acquire data related to each component provided in the system at regular time intervals according to a predetermined cycle, taking into account the computational load.

[0086] The control unit (260) can perform various operations based on the acquired data and control the overall operation of each component provided in the system according to the operation results.

[0087] Data related to each component provided in the system may include, for example, the operating frequency of the compressor (251), the suction temperature of the compressor (251), the discharge temperature, the suction pressure, the discharge pressure, the concentration of oil stored inside the compressor (251), the amount of oil, the inlet-side pipe temperature of the indoor unit (IDU), the outlet-side pipe temperature of the indoor unit (IDU), the indoor temperature, the outdoor temperature, the opening amount of the electronic expansion valve (EEV), etc.

[0088] Meanwhile, the system may further include an input device (not shown) capable of receiving user input. For example, when the system receives user input via an input device (e.g., a touch panel, keys, etc.), it may perform an action corresponding to the received user input.

[0089] The system may further include an output device (270) that outputs a message regarding the operating status of the system. For example, the output device (270) may include a display device such as a display, a light emitting diode (LED), and / or an audio device such as a speaker or buzzer.

[0090] FIG. 3 is a block diagram of a sensor according to one embodiment of the present disclosure.

[0091] Referring to FIG. 3, the oil sensor (300) may include an electrode assembly (310) and / or a processing circuit (320).

[0092] The electrode assembly (310) may include a plurality of electrodes. Some of the plurality of electrodes included in the electrode assembly (310) may be formed to extend vertically. Others of the plurality of electrodes included in the electrode assembly (310) may be formed to extend horizontally.

[0093] The electrode assembly (310) may be disposed inside the compressor (1). The electrode assembly (310) may be exposed to a fluid stored inside the compressor (1). At least some of the plurality of electrodes included in the electrode assembly (310) may be disposed to be immersed in the fluid. The fluid stored inside the compressor (1) may include at least oil. The fluid stored inside the compressor (1) may further include a refrigerant.

[0094] A voltage may be applied to the electrode assembly (310). A sensing voltage may be applied to some of the plurality of electrodes included in the electrode assembly (310). The sensing voltage may be an alternating voltage whose voltage value periodically changes. The sensing voltage may have a predetermined frequency. A ground voltage may be applied to other some of the plurality of electrodes included in the electrode assembly (310).

[0095] The processing circuit (320) can be electrically connected to the electrode assembly (310). The processing circuit (320) can apply voltage to the electrode assembly (310).

[0096] The processing circuit (320) can detect electrostatic capacitance based on the voltage applied to the electrode assembly (310).

[0097] For example, the processing circuit (320) can detect the electrostatic capacitance corresponding to a first electrode to which a sensing voltage is applied and a second electrode to which a ground voltage is applied among the plurality of electrodes included in the electrode assembly (310) through a mutual capacitance method. The electrostatic capacitance corresponding to two electrodes among the plurality of electrodes can be detected based on mathematical expression 1.

[0098]

[0099] Here, C is the electrostatic capacitance, is the permittivity corresponding to vacuum, where is the dielectric constant corresponding to the material between the two electrodes, d is the distance between the two electrodes, and A is the area of ​​the electrode in contact with the material.

[0100] For example, the processing circuit (320) can detect the electrostatic capacitance corresponding to one electrode to which a sensing voltage is applied among the plurality of electrodes included in the electrode assembly (310). At this time, the processing circuit (320) can detect the electrostatic capacitance corresponding to one electrode to which the sensing voltage is applied through a self-capacitance method (i.e., a proximity method).

[0101] The processing circuit (320) can calculate the concentration of oil contained in the fluid stored inside the compressor (1) based on the electrostatic capacitance of the electrode assembly (310). The processing circuit (320) can calculate the height of the surface of the fluid stored inside the compressor (1) based on the electrostatic capacitance of the electrode assembly (310). The processing circuit (320) can calculate the amount of the fluid stored inside the compressor (1) based on the electrostatic capacitance of the electrode assembly (310).

[0102] The processing circuit (320) may include a capacitance detection circuit (321) that detects the capacitance for the electrode assembly (310). The processing circuit (320) may include a control circuit (323) that calculates the concentration of oil, the height of the surface of the fluid, and / or the amount of the fluid. The capacitance detection circuit (321) and the control circuit (323) may be implemented as a single configuration or may be implemented as separate configurations. Meanwhile, the capacitance detection circuit (321) and / or the control circuit (323) may be included in the control unit (260) of the system.

[0103] FIGS. 4A to 6B are drawings illustrating the configuration of an electrode assembly according to embodiments of the present disclosure.

[0104] Referring to FIGS. 4A to 6B, the electrode assembly (310) may include an upper electrode (410), a shield electrode (420), and a lower electrode assembly (430).

[0105] The upper electrode (410) may be formed to extend horizontally. The upper electrode (410) may be formed to have a first width (w1) in the left-right direction. The upper electrode (410) may be formed to have a first length (l1) in the front-back direction. The upper electrode (410) may be formed to have a first height in the up-down direction.

[0106] The upper electrode (410) may be arranged so that the upper surface having the first width (w1) and the first length (l1) faces upward. The upper electrode (410) may be arranged so that the lower surface having the first width (w1) and the first length (l1) faces downward.

[0107] A sensing voltage can be applied to the upper electrode (410). The capacitance corresponding to the upper electrode (410) can be detected using a self-capacitance method. When the height of the surface (400) of the fluid changes, the amount of fluid present between the upper plane of the upper electrode (410) and the surface (400) of the fluid can change. Here, the height of the surface (400) of the fluid can correspond to the distance between the upper electrode (410) and the surface (400) of the fluid.

[0108] At this time, the electrostatic capacitance corresponding to the upper electrode (410) may vary in response to a change in the amount of fluid existing between the upper plane of the upper electrode (410) and the surface (400) of the fluid. That is, the electrostatic capacitance corresponding to the upper electrode (410) may correspond to the height of the surface (400) of the fluid. In addition, the electrostatic capacitance corresponding to the upper electrode (410) may correspond to the amount of fluid stored inside the compressor (251).

[0109] The electrostatic capacitance corresponding to the upper electrode (410) may correspond to the concentration of oil contained in the fluid existing between the upper electrode (410) and the surface (400) of the fluid. For example, the higher the concentration of oil, the smaller the change in the electrostatic capacitance corresponding to the upper electrode (410) according to the height of the surface (400) of the fluid may be. Therefore, since the electrostatic capacitance corresponding to the upper electrode (410) varies depending on the concentration of oil, the control circuit (323) can first determine the concentration of oil and then determine the height of the surface of the fluid based on the concentration of oil. In addition, the control circuit (323) can determine the amount of fluid in response to the determination of the height of the surface of the fluid.

[0110] The shield electrode (420) can be formed to extend horizontally.

[0111] The shield electrode (420) may be formed to have a second width (w2) in the left-right direction. The second width (w2) of the shield electrode (420) may correspond to the first width (w1) of the upper electrode (410). For example, the second width (w2) of the shield electrode (420) may be greater than or equal to the first width (w1) of the upper electrode (410).

[0112] The shield electrode (420) may be formed to have a second length (l2) along the front-back direction. The second length (l2) of the shield electrode (420) may correspond to the first length (l1) of the upper electrode (410). For example, the second length (l2) of the shield electrode (420) may be greater than or equal to the first length (l1) of the upper electrode (410).

[0113] The shield electrode (420) can be formed to have a second height along the vertical direction.

[0114] The shield electrode (420) may be positioned below the upper electrode (410). The shield electrode (420) may be positioned corresponding to the upper electrode (410). The size of the upper electrode (410) in the horizontal direction may be smaller than the size of the shield electrode (420). For example, when looking at the upper surface of the upper electrode (410) in the downward direction, the upper surface of the upper electrode (410) may be located on the inner side of the shield electrode (420).

[0115] The shield electrode (420) may be arranged so that at least a portion thereof is immersed in the fluid stored inside the compressor (1). In the case where a minimum amount of fluid is stored inside the compressor (1), the surface (400) of the fluid may be located above the lower surface of the shield electrode (420). That is, the shield electrode (420) may be arranged so that the lower surface of the shield electrode (420) is immersed in the fluid stored inside the compressor (1).

[0116] The lower electrode assembly (430) may be positioned below the shield electrode (420). As the lower electrode assembly (430) is positioned below the shield electrode (420), the lower electrode assembly (430) may be positioned to be immersed in the fluid stored inside the compressor (1). That is, in the case where a minimum amount of fluid is stored inside the compressor (1), the surface (400) of the fluid may be located above the lower electrode assembly (430).

[0117] The lower electrode assembly (430) may be arranged to correspond to the shield electrode (420). The shield electrode (420) may be arranged to cover the lower electrode assembly (430) from above. That is, the size of the lower electrode assembly (430) in the horizontal direction may be smaller than the size of the shield electrode (420). For example, when looking at the lower surface of the shield electrode (420) in an upward direction, the lower electrode assembly (430) may be located on the inside of the shield electrode (420).

[0118] As the shield electrode (420) is positioned on the upper side of the lower electrode assembly (430) to cover the lower electrode assembly (430), the influence of the upper electrode (410) on the lower electrode assembly (430) can be reduced. In addition, as the shield electrode (420) is positioned on the upper side of the lower electrode assembly (430) to cover the lower electrode assembly (430), the influence of a change in the height of the surface (400) of the fluid on the lower electrode assembly (430) can be reduced.

[0119] The lower electrode assembly (430) may include at least one lower electrode to which a sensing voltage is applied. The lower electrode assembly (430) may further include a ground electrode (433) to which a ground voltage is applied.

[0120] Referring to FIGS. 4A and 4B, the lower electrode assembly (430) may include a first lower electrode (431).

[0121] As shown in Fig. 4a, the first lower electrode (431) may be formed to extend vertically. The first lower electrode (431) may be formed to have a third height (h3) along the vertical direction. The first lower electrode (431) may be formed to have a third length (l3) along the front-back direction.

[0122] Meanwhile, as shown in Fig. 4b, the first lower electrode (431) may be formed to extend horizontally. The first lower electrode (431) may be formed to have a third width (w3) along the left-right direction. The first lower electrode (431) may be formed to have a third length (l3) along the front-back direction.

[0123] The electrostatic capacitance corresponding to the first lower electrode (431) can be detected using the self-capacitance method. At this time, since the first lower electrode (431) is always immersed in the fluid, the electrostatic capacitance corresponding to the first lower electrode (431) can correspond to the concentration of oil contained in the fluid. That is, the sensor (300) can determine the concentration of oil contained in the fluid based on the electrostatic capacitance corresponding to the first lower electrode (431).

[0124] Referring to FIGS. 5A and 5B, the lower electrode assembly (430) may include a ground electrode (433).

[0125] As shown in Fig. 5a, the ground electrode (433) may be formed to be vertically elongated. The ground electrode (433) may be formed to have a fourth height (h4) in the vertical direction. The ground electrode (433) may be formed to have a fourth length (l4) in the front-back direction. For example, the fourth height (h4) of the ground electrode (433) may correspond to the third length (h3) of the first lower electrode (431). For example, the fourth length (l4) of the ground electrode (433) may correspond to the third length (l3) of the first lower electrode (431).

[0126] Meanwhile, as shown in Fig. 5b, the first lower electrode (431) may be formed to extend horizontally. The ground electrode (433) may be formed to have a fourth width (w4) along the left-right direction.

[0127] The electrostatic capacitance corresponding to the first lower electrode (431) can be detected using the mutual capacitance method for the first lower electrode (431) and the ground electrode (433). At this time, since the first lower electrode (431) and the ground electrode (433) are always immersed in the fluid, the electrostatic capacitance corresponding to the first lower electrode (431) can correspond to the concentration of oil contained in the fluid. That is, the sensor (300) can determine the concentration of oil contained in the fluid based on the electrostatic capacitance corresponding to the first lower electrode (431).

[0128] Referring to FIGS. 6A and 6B, the lower electrode assembly (430) may include a second lower electrode (435).

[0129] As shown in Fig. 6a, the second lower electrode (435) may be formed to be vertically extended. The second lower electrode (435) may be formed to have a fifth height (h5) in the vertical direction. The second lower electrode (435) may be formed to have a fifth length (l5) in the front-back direction. For example, the fifth length (l5) of the second lower electrode (435) may correspond to the third length (l3) of the first lower electrode (431) and the fourth length (l4) of the ground electrode (433). For example, the fifth height (h5) of the second lower electrode (435) may be different from the third height (h3) of the first lower electrode (431).

[0130] Meanwhile, as shown in FIG. 6b, the second lower electrode (435) may be formed to extend horizontally. The second lower electrode (435) may be formed to have a fifth width (w5) in the left-right direction. The second lower electrode (435) may be formed to have a fifth length (l5) in the front-back direction. For example, the fifth width (w5) of the second lower electrode (435) may be different from the third width (w3) of the first lower electrode (431).

[0131] The electrostatic capacitance corresponding to the first lower electrode (431) can be detected using the mutual capacitance method for the first lower electrode (431) and the ground electrode (433). Since the first lower electrode (431) and the ground electrode (433) are immersed in the fluid, the electrostatic capacitance corresponding to the first lower electrode (431) and the ground electrode (433) can correspond to the concentration of oil contained in the fluid.

[0132] The electrostatic capacitance corresponding to the second lower electrode (435) can be detected using the mutual capacitance method for the second lower electrode (435) and the ground electrode (433). Since the second lower electrode (435) and the ground electrode (433) are immersed in the fluid, the electrostatic capacitance corresponding to the second lower electrode (435) and the ground electrode (433) can correspond to the concentration of oil contained in the fluid.

[0133] As shown in Fig. 6a, in a case where the first lower electrode (431) and the second lower electrode (435) are formed to be vertically extended, since the third height (h3) of the first lower electrode (431) and the fifth height (h5) of the second lower electrode (435) are different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0134] At this time, if the oil concentration with respect to the depth of the fluid facing downward is different depending on the depth of the fluid, the difference in the oil concentration with respect to the depth of the fluid may affect the difference between the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435).

[0135] The electrostatic capacitance corresponding to the first lower electrode (431) may correspond to the oil concentration for the depth of the fluid corresponding to the third height (h3). The electrostatic capacitance corresponding to the second lower electrode (435) may correspond to the oil concentration for the depth of the fluid corresponding to the fifth height (h5).

[0136] According to one embodiment, the control circuit (323) can determine the oil concentration corresponding to the depth of the fluid. For example, the control circuit (323) can determine the oil concentration for the depth of the fluid corresponding to the fifth height (h5) based on the electrostatic capacity corresponding to the second lower electrode (435). In this case, the control circuit (323) can determine the oil concentration for the depth of the fluid corresponding to the third height (h3) based on the electrostatic capacity corresponding to the first lower electrode (431) and the oil concentration for the depth of the fluid corresponding to the fifth height (h5).

[0137] Meanwhile, in a case where the first lower electrode (431) and the second lower electrode (435) are formed to be extended horizontally as in FIG. 6b, since the third width (w3) of the first lower electrode (431) and the fifth width (w5) of the second lower electrode (435) are different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0138] The capacitance corresponding to the first lower electrode (431) may correspond to the concentration of oil for the depth of the fluid corresponding to the third width (w3) of the first lower electrode (431). The capacitance corresponding to the second lower electrode (435) may correspond to the concentration of oil for the depth of the fluid corresponding to the fifth width (w5) of the second lower electrode (435). For example, when the third width (w3) is greater than the fifth width (w5), the depth of the fluid corresponding to the third width (w3) may be greater than the depth of the fluid corresponding to the fifth width (w5).

[0139] According to one embodiment, the control circuit (323) can determine the oil concentration corresponding to the depth of the fluid. For example, the control circuit (323) can determine the oil concentration for the depth of the fluid corresponding to the third width (w3) based on the electrostatic capacitance corresponding to the first lower electrode (431). For example, the control circuit (323) can determine the oil concentration for the depth of the fluid corresponding to the fifth width (w5) based on the electrostatic capacitance corresponding to the second lower electrode (435).

[0140] Referring to FIG. 7, when the first concentration of oil corresponding to the first depth (d1) of the fluid and the second concentration of oil corresponding to the second depth (d2) of the fluid are different from each other, the control circuit (323) can determine the concentration of oil corresponding to the surface (d0) of the fluid based on the first concentration of oil and the second concentration of oil. For example, the control circuit (323) can determine the concentration of oil corresponding to the surface (d0) of the fluid based on the difference between the first concentration and the second concentration with respect to the difference between the first depth (d1) and the second depth (d2). For example, the control circuit (323) can determine the concentration of oil corresponding to the surface (d0) of the fluid based on data about the concentration of oil corresponding to the surface (d0) of the fluid corresponding to the first concentration, the second concentration, and the difference between the first concentration and the second concentration.

[0141] Accordingly, according to various embodiments of the present disclosure, the control circuit (323) can first determine the concentration of the oil, and then determine the height of the surface of the fluid based on the concentration of the oil. For example, the control circuit (323) can determine the concentration of the oil based on the electrostatic capacitance corresponding to the first lower electrode (431), and then determine the height of the surface of the fluid based on the determined concentration of the oil. For example, the control circuit (323) can determine the concentration of the oil based on the electrostatic capacitance corresponding to the second lower electrode (435), and then determine the height of the surface of the fluid based on the determined concentration of the oil. For example, the control circuit (323) can determine the concentration of the oil corresponding to the surface (d0) of the fluid based on the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435), and then determine the height of the surface of the fluid based on the determined concentration of the oil.

[0142] According to one embodiment, a sensing voltage may be applied to the shield electrode (420). That is, the shield electrode (420) may be configured for active shielding.

[0143] Referring to FIG. 8, when looking at the output of the sensor in the time domain, the noise included in the output of the sensor can be significantly reduced when there is a configuration for passive shielding (802) or a configuration for active shielding (803), compared to when there is no configuration for passive shielding or active shielding (801).

[0144] Meanwhile, referring to FIG. 9, when examining the output of the sensor in the frequency domain, when there is a configuration for passive shielding (902), the noise peak at a given frequency (e.g., 50 Hz) can be reduced compared to when there is no configuration for passive shielding or active shielding (801). In addition, when there is a configuration for active shielding (903), the noise peak at a given frequency (e.g., 50 Hz) can be further reduced compared to when there is a configuration for passive shielding (902).

[0145] In this way, when a sensing voltage is applied to the shield electrode (420), no potential difference occurs between the shield electrode (420) and the lower electrodes (431, 435), so that parasitic capacitance can be eliminated. Accordingly, due to the elimination of parasitic capacitance, the signal-to-noise ratio (SNR) can be improved.

[0146] FIGS. 10 to 17 are drawings illustrating the configuration of an electrode assembly according to embodiments of the present disclosure.

[0147] Referring to FIGS. 10 to 17, according to embodiments of the present disclosure, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different from each other depending on the shape, size, position, separation distance from other components, etc. of each of the first lower electrode (431) and the second lower electrode (435). At this time, the difference between the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may correspond to the difference in the concentration of oil with respect to the depth of the fluid directed downward. Accordingly, the sensor (300) may determine the concentration of oil corresponding to the depth of the fluid based on the electrostatic capacitance corresponding to the first lower electrode (431), the electrostatic capacitance corresponding to the second lower electrode (435), and / or the difference between the two electrostatic capacitances.

[0148] Referring to FIG. 10, the lower electrode assembly (430) may include a first lower electrode (431) and a second lower electrode (435). The first lower electrode (431) and the second lower electrode (435) may be formed to extend horizontally.

[0149] The first lower electrode (431) and the second lower electrode (435) may be arranged vertically apart from the shield electrode (420) by a predetermined distance (d). The first lower electrode (431) and the second lower electrode (435) may be arranged side by side in the horizontal direction.

[0150] Referring to drawing reference numeral 1001 of FIG. 10, the third width (w3) of the first lower electrode (431) may be different from the fifth width (w5) of the second lower electrode (435).

[0151] The capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to each of the second lower electrodes (435) can be detected using the self-capacitance method. At this time, since the third width (w3) of the first lower electrode (431) and the fifth width (w5) of the second lower electrode (435) are different, the capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to the second lower electrode (435) may be different.

[0152] Referring to drawing reference numeral 1002 of FIG. 10, the third width (w3) of the first lower electrode (431) may be different from the fifth width (w5) of the second lower electrode (435).

[0153] A ground electrode (433) may be placed between the first lower electrode (431) and the second lower electrode (435).

[0154] The capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to each of the second lower electrodes (435) can be detected using a mutual capacitance method with respect to the ground electrode (433). At this time, since the third width (w3) of the first lower electrode (431) and the fifth width (w5) of the second lower electrode (435) are different, the capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to the second lower electrode (435) may be different.

[0155] Referring to drawing reference numeral 1003 of FIG. 10, the third width (w3) of the first lower electrode (431) and the fifth width (w5) of the second lower electrode (435) may correspond.

[0156] A ground electrode (433) may be placed between the first lower electrode (431) and the second lower electrode (435). With respect to the horizontal direction, the distance (ds1) between the first lower electrode (431) and the ground electrode (433) and the distance (ds2) between the second lower electrode (435) and the ground electrode (433) may be different.

[0157] The capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to each of the second lower electrodes (435) can be detected using a mutual capacitance method with respect to the ground electrode (433). At this time, since the distance (ds1) between the first lower electrode (431) and the ground electrode (433) and the distance (ds2) between the second lower electrode (435) and the ground electrode (433) are different, the capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to the second lower electrode (435) may be different.

[0158] Referring to FIGS. 11 and 12, the lower electrode assembly (430) may include a first lower electrode (431) and a second lower electrode (435). The first lower electrode (431) and the second lower electrode (435) may be formed to extend vertically.

[0159] The first lower electrode (431) and the second lower electrode (435) may be arranged vertically apart from the shield electrode (420) by a predetermined distance (d). The first lower electrode (431) and the second lower electrode (435) may be arranged side by side in the horizontal direction.

[0160] Referring to drawing reference numeral 1101 of FIG. 11, the third height (h3) of the first lower electrode (431) may be different from the fifth height (h5) of the second lower electrode (435).

[0161] The capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to each of the second lower electrodes (435) can be detected using the self-capacitance method. At this time, since the third height (h3) of the first lower electrode (431) and the fifth height (h5) of the second lower electrode (435) are different, the capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to the second lower electrode (435) may be different.

[0162] Referring to drawing reference numeral 1102 of FIG. 11, the third height (h3) of the first lower electrode (431) may be different from the fifth height (h5) of the second lower electrode (435).

[0163] A ground electrode (433) may be placed between the first lower electrode (431) and the second lower electrode (435).

[0164] The capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to each of the second lower electrodes (435) can be detected using a mutual capacitance method with respect to the ground electrode (433). At this time, since the third height (h3) of the first lower electrode (431) and the fifth height (h5) of the second lower electrode (435) are different, the capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to the second lower electrode (435) may be different.

[0165] Referring to FIG. 12, the third height (h3) of the first lower electrode (431) and the fifth height (h5) of the second lower electrode (435) can correspond.

[0166] A ground electrode (433) may be placed between the first lower electrode (431) and the second lower electrode (435). With respect to the horizontal direction, the distance (ds1) between the first lower electrode (431) and the ground electrode (433) and the distance (ds2) between the second lower electrode (435) and the ground electrode (433) may be different.

[0167] The capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to each of the second lower electrodes (435) can be detected using a mutual capacitance method with respect to the ground electrode (433). At this time, since the distance (ds1) between the first lower electrode (431) and the ground electrode (433) and the distance (ds2) between the second lower electrode (435) and the ground electrode (433) are different, the capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to the second lower electrode (435) may be different.

[0168] Referring to FIG. 13, the lower electrode assembly (430) may include a first lower electrode (431) and a second lower electrode (435). The first lower electrode (431) and the second lower electrode (435) may be formed to extend horizontally.

[0169] The third width (w3) of the first lower electrode (431) and the fifth width (w5) of the second lower electrode (435) may correspond to each other or may be different.

[0170] The first lower electrode (431) may be arranged vertically apart from the shield electrode (420) by a first distance (d1). The second lower electrode (435) may be arranged vertically apart from the shield electrode (420) by a second distance (d2). That is, the depth of the fluid directed downward may be different corresponding to the positions where the first lower electrode (431) and the second lower electrode (435) are arranged, respectively.

[0171] Referring to drawing symbol 1301, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to each of the second lower electrodes (435) can be detected using a self-capacitance method. At this time, since the depth of the fluid corresponding to the positions where the first lower electrode (431) and the second lower electrode (435) are respectively placed is different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0172] Referring to drawing symbol 1302, a ground electrode (433) may be placed between the first lower electrode (431) and the second lower electrode (435) in the horizontal direction.

[0173] When the first distance (d1) at which the first lower electrode (431) and the shield electrode (420) are spaced apart exceeds the second distance (d2) at which the second lower electrode (435) and the shield electrode (420) are spaced apart, the fourth height (h4) of the ground electrode (433) may be greater than or equal to the distance at which the lower surface of the first lower electrode (431) and the upper surface of the second lower electrode (435) are spaced apart.

[0174] The electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to each of the second lower electrodes (435) can be detected using a mutual capacitance method with respect to the ground electrode (433). At this time, since the depths of the fluid corresponding to the positions where the first lower electrode (431) and the second lower electrode (435) are respectively placed are different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0175] Referring to FIG. 14, the lower electrode assembly (430) may include a first lower electrode (431) and a second lower electrode (435). The first lower electrode (431) and the second lower electrode (435) may be formed to extend vertically.

[0176] The third height (h3) of the first lower electrode (431) and the fifth height (h5) of the second lower electrode (435) may correspond to each other or may be different.

[0177] The first lower electrode (431) may be arranged vertically apart from the shield electrode (420) by a first distance (d1). The second lower electrode (435) may be arranged vertically apart from the shield electrode (420) by a second distance (d2). That is, the depth of the fluid directed downward may be different corresponding to the positions where the first lower electrode (431) and the second lower electrode (435) are arranged, respectively.

[0178] Referring to drawing reference numeral 1401, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to each of the second lower electrodes (435) can be detected using a self-capacitance method. At this time, since the depth of the fluid corresponding to the positions where the first lower electrode (431) and the second lower electrode (435) are respectively placed is different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0179] Referring to drawing symbol 1402, a ground electrode (433) may be placed between the first lower electrode (431) and the second lower electrode (435) in the horizontal direction.

[0180] When the first distance (d1) at which the first lower electrode (431) and the shield electrode (420) are spaced apart exceeds the second distance (d2) at which the second lower electrode (435) and the shield electrode (420) are spaced apart, the fourth height (h4) of the ground electrode (433) may be greater than or equal to the distance at which the lower surface of the first lower electrode (431) and the upper surface of the second lower electrode (435) are spaced apart.

[0181] The electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to each of the second lower electrodes (435) can be detected using a mutual capacitance method with respect to the ground electrode (433). At this time, since the depths of the fluid corresponding to the positions where the first lower electrode (431) and the second lower electrode (435) are respectively placed are different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0182] Referring to FIG. 15, the lower electrode assembly (430) may include a first lower electrode (431) and a second lower electrode (435). The first lower electrode (431) and the second lower electrode (435) may be formed to extend horizontally.

[0183] The third width (w3) of the first lower electrode (431) and the fifth width (w5) of the second lower electrode (435) may correspond to each other or may be different. The third height (h3) of the first lower electrode (431) and the fifth height (h5) of the second lower electrode (435) may correspond to each other or may be different.

[0184] The first lower electrode (431) may be arranged vertically apart from the shield electrode (420) by a first distance (d1). The second lower electrode (435) may be arranged vertically apart from the shield electrode (420) by a second distance (d2). That is, the depth of the fluid directed downward may be different corresponding to the positions where the first lower electrode (431) and the second lower electrode (435) are arranged, respectively.

[0185] The electrode assembly (310) may further include a sub-shield electrode (425). The sub-shield electrode (425) may be formed to extend horizontally.

[0186] The sub-shield electrode (425) may be formed to have a sixth width (w6) in the left-right direction. When the first lower electrode (431) is arranged on the left side and the second lower electrode (435) is arranged on the right side, the sixth width (w6) of the sub-shield electrode (425) may be greater than or equal to the distance between the left side of the first lower electrode (431) and the right side of the second lower electrode (435).

[0187] The sub-shield electrode (425) may be formed to have a sixth length in the front-back direction. The sixth length of the sub-shield electrode (425) may correspond to the third length (l3) of the first lower electrode (431) and the fifth length (l5) of the second lower electrode (435).

[0188] According to one embodiment, a sensing voltage may be applied to the sub-shield electrode (425). That is, the sub-shield electrode (425) may be configured for active shielding.

[0189] The electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to each of the second lower electrodes (435) can be detected using the self-capacitance method. At this time, since the depth of the fluid corresponding to the positions where each of the first lower electrode (431) and the second lower electrode (435) is placed is different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0190] Referring to FIGS. 16 and 17, the lower electrode assembly (430) may include a first lower electrode (431) and a second lower electrode (435). The first lower electrode (431) and the second lower electrode (435) may be formed to extend vertically.

[0191] The third height (h3) of the first lower electrode (431) and the fifth height (h5) of the second lower electrode (435) may correspond to each other or may be different.

[0192] The first lower electrode (431) and the second lower electrode (435) may be arranged vertically apart from the shield electrode (420) by a predetermined distance (d). The first lower electrode (431) and the second lower electrode (435) may be arranged side by side in the horizontal direction.

[0193] The shape of the first lower electrode (431) and the shape of the second lower electrode (435) may be different. The shape of the first lower electrode (431) and the shape of each of the second lower electrodes (435) may correspond to the surrounding environment in which the sensor (300) is placed, the internal structure of the sensor (300) in which the lower electrode assembly (430) is placed, etc.

[0194] For example, referring to FIG. 16, the lower end of the first lower electrode (431) may be formed to extend in the left direction by a first extension length (e1). For example, referring to FIG. 17, the first lower electrode (431) may be formed to extend in the left and downward directions by a second extension length (e2).

[0195] Referring to drawing reference numeral 1601 of FIG. 16 and drawing reference numeral 1701 of FIG. 17, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to each of the second lower electrodes (435) can be detected using a self-capacitance method. At this time, since the shape of the first lower electrode (431) and the shape of the second lower electrode (435) are different, the electrostatic capacitance corresponding to the first lower electrode (431) and the electrostatic capacitance corresponding to the second lower electrode (435) may be different.

[0196] Referring to drawing reference numeral 1602 of FIG. 16 and drawing reference numeral 1702 of FIG. 17, a ground electrode (433) may be placed between the first lower electrode (431) and the second lower electrode (435).

[0197] The capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to each of the second lower electrodes (435) can be detected using a mutual capacitance method with respect to the ground electrode (433). At this time, since the shape of the first lower electrode (431) and the shape of the second lower electrode (435) are different, the capacitance corresponding to the first lower electrode (431) and the capacitance corresponding to the second lower electrode (435) may be different.

[0198] FIGS. 18 to 23 are drawings illustrating a sensing module of a sensor according to one embodiment of the present disclosure.

[0199] Referring to FIGS. 18 to 21, the sensor (300) may include a sensing module (400S). The sensing module (400S) may include an electrode assembly (310), a housing (440), and a pin assembly (450).

[0200] For example, the electrode assembly (310) may be installed at the bottom of the compressor (1, see FIGS. 1A and 1B). The electrode assembly (310) may be inserted into the interior of the compressor (1), and the pin assembly (450) may be electrically connected to a processing circuit (320, see FIG. 3) outside the compressor (1) via a cable.

[0201] The housing (440) may have an overall cap shape. The housing (440) may be referred to as a cap (440). The housing (440) may be opened toward the electrode assembly (310). The bottom (441) of the housing (440) may have a circular shape. Alternatively, the bottom (441) of the housing (440) may have an angular shape (e.g., a square, a pentagon, etc.). The side wall (442) of the housing (440) may extend along the edge of the bottom (441) of the housing (440). The flange (443) of the housing (440) may protrude from the side of the side wall (442) and may extend along the side wall (442). The diameter (width) of the flange (443) of the housing (440) may be larger than the diameter (width) of the side wall (442) of the housing (440). The flange (443) of the housing (440) may be adjacent to an end of the side wall (442). The housing (440) may penetrate the body (1W) of the compressor (1). The flange (443) of the housing (440) may face the inner surface of the body (1W) of the compressor (1), and the side wall (442) of the housing (440) may be welded to the body (1W) of the compressor (1).

[0202] The electrode assembly (310) may face the bottom (441) of the housing (440). The electrode assembly (310) may be spaced apart from the bottom (441) of the housing (440) and may extend in a direction intersecting the bottom (441). The electrode assembly (310) may include a material having electrical conductivity, such as metal. The electrode assembly (310) may include an upper electrode (410), a shield electrode (420), and a lower electrode assembly (430). The upper electrode (410) may be referred to as a liquid level detector (410). The lower electrode assembly (430) may be referred to as a concentration detector (430).

[0203] The upper electrode (410) may have a plate shape extending horizontally. The upper electrode (410) may have an overall rectangular shape. The upper electrode (410) may have two long sides that are opposite to each other and two short sides that are opposite to each other. The first protrusion (411a) may protrude from the first short side (411) of the upper electrode (410) and may form one end of the upper electrode (410). The second protrusion (412a) may protrude from the second short side (412) of the upper electrode (410) and may form the other end of the upper electrode (410). The portion of the upper electrode (410) between the protrusions (411a, 412a) may be referred to as an upper body (4100) and may have a length and width greater than the protrusions (411a, 412a).

[0204] The shield electrode (420) may be spaced downward from the upper electrode (410). The shield electrode (420) may have a plate shape extending horizontally. The shield electrode (420) may have two long sides that are opposite to each other and two short sides that are opposite to each other. The first protrusion (421a) may protrude from the first short side (421) of the shield electrode (420) and may form one end of the shield electrode (420). The second protrusion (422a) may protrude from the second short side (422) of the shield electrode (420) and may form the other end of the shield electrode (420). The portion of the shield electrode (420) between the protrusions (421a, 422a) may be referred to as a shield body (4200) and may have a length and width greater than the protrusions (421a, 422a). The length and width of the shield body (4200) may be greater than or equal to the length and width of the upper body (4100). That is, the area of ​​the shield body (4200) may be greater than or equal to the area of ​​the upper body (4100). The shield body (4200) may cover the lower surface of the upper body (4100).

[0205] The lower electrode assembly (430) may be spaced downward from the shield electrode (420). The lower electrode assembly (430) may have a plate shape extending in a direction intersecting the shield electrode (420). The lower electrode assembly (430) may extend in a longitudinal direction of the shield electrode (420). Here, the longitudinal direction of the shield electrode (420) may be a direction parallel to long sides of the shield electrode (420). The electrodes of the lower electrode assembly (430) may be spaced apart from each other in the horizontal direction. The lower electrode assembly (430) may include a first lower electrode (431), a second lower electrode (435), and a ground electrode (433).

[0206] The first lower electrode (431) may have a plate shape perpendicular to the shield electrode (420). The first lower electrode (431) may have an overall rectangular shape. The first lower electrode (431) may have two long sides that are opposite to each other and two short sides that are opposite to each other. The first long side of the first lower electrode (431) may be adjacent to the lower surface of the shield electrode (420). The first protrusion (4311a) may protrude from the first short side (4311) of the first lower electrode (431) and form one end of the first lower electrode (431). The second protrusion (4312a) may protrude from the second short side (4312) of the first lower electrode (431) and may form the other end of the first lower electrode (431). A portion of the first lower electrode (431) between the protrusions (4311a, 4312a) may be referred to as a first lower body (4310) and may have a length and width greater than those of the protrusions (4311a, 4312a). The length of the first lower body (4310) may be less than or equal to the length of the shield body (4200), and the shield body (4200) may cover an upper edge of the first lower body (4310).

[0207] The second lower electrode (435) may have a plate shape perpendicular to the shield electrode (420). The second lower electrode (435) may be spaced apart horizontally from the first lower electrode (431). The second lower electrode (435) may have an overall rectangular shape. The second lower electrode (435) may have two long sides that are opposite to each other and two short sides that are opposite to each other. The first long side of the second lower electrode (435) may be adjacent to the lower surface of the shield electrode (420). The first protrusion (4351a) may protrude from the first short side (4351) of the second lower electrode (435) and form one end of the second lower electrode (435). The second protrusion (4352a) may protrude from the second short side (4352) of the second lower electrode (435) and form the other end of the second lower electrode (435). A portion of the second lower electrode (435) between the protrusions (4351a, 4352a) may be referred to as a second lower body (4350) and may have a length and width greater than those of the protrusions (4351a, 4352a). The length of the second lower body (4350) may be less than or equal to the length of the shield body (4200), and the shield body (4200) may cover an upper edge of the second lower body (4350).

[0208] The ground electrode (433) may have a plate shape perpendicular to the shield electrode (420). The ground electrode (433) may be disposed between the first lower electrode (431) and the second lower electrode (435), and may be horizontally spaced from the first lower electrode (431) and the second lower electrode (435). The ground electrode (433) may have an overall rectangular shape. The ground electrode (433) may have two long sides that are opposite to each other, and two short sides that are opposite to each other. The first long side of the ground electrode (433) may be adjacent to the lower surface of the shield electrode (420). The first protrusion (4331a) may protrude from the first short side (4331) of the ground electrode (433) and may form one end of the ground electrode (433). The second protrusion (4332a) may protrude from the second short side (4332) of the ground electrode (433) and may form the other end of the ground electrode (433). A portion of the ground electrode (433) between the protrusions (4331a, 4332a) may be referred to as a ground body (4330) and may have a length and width greater than those of the protrusions (4331a, 4332a). The length of the ground body (4330) may be less than or equal to the length of the shield body (4200), and the shield body (4200) may cover an upper edge of the ground body (4330).

[0209] Accordingly, the shield electrode (420) can be placed between the upper electrode (410) and the lower electrode assembly (430), and can shield the upper electrode (410) from the lower electrode assembly (430) while shielding the lower electrode assembly (430) from the upper electrode (410).

[0210] Referring to FIGS. 22 and 23, the pin assembly (450) may penetrate the bottom (441) of the housing (440). The pin assembly (450) may include an electrically conductive material, such as metal. The side wall (442) of the housing (440) may surround the pin assembly (450). A rib (441r) protruding from the inner surface of the bottom (441) may surround a portion of the outer surface of the pin assembly (450). A sealant (441s) may close a gap between the outer surface of the pin assembly (450) and the inner surface of the rib (441r). The sealant (441s) may be made of an electrically insulating material, such as glass. The sealant (441s) may be referred to as an insulation material (441s) or a glass frit (441s).

[0211] The pin assembly (450) may include a plurality of pins. The pins may be electrically conductive. The pins may be referred to as conductive pins. The number of the pins may be equal to the number of electrodes of the electrode assembly (310). Alternatively, the number of the pins may be one less than the number of electrodes of the electrode assembly (310). That is, the pin assembly (450) may include pins connected to the upper electrode (410) and the lower electrode assembly (430), and may or may not include a pin connected to the shield electrode (420).

[0212] For example, the pin assembly (450) may include a first pin (451), a second pin (452), a third pin (453), a fourth pin (454), and a fifth pin (455). The first to fifth pins (451, 452, 453, 454, 455) may extend in a direction intersecting the bottom (441) of the housing (440). The first to fifth pins (451, 452, 453, 454, 455) may be arranged adjacent to and along an edge of the bottom (441) of the housing (440). That is, the first to fifth pins (451, 452, 453, 454, 455) may be arranged radially with respect to the center of the bottom (441) of the housing (440). The first pin (451) may be electrically connected to the upper electrode (410). The second pin (452) may be electrically connected to the shield electrode (420). The third pin (453) may be electrically connected to the first lower electrode (431). The fourth pin (454) may be electrically connected to the second lower electrode (435). The fifth pin (455) may be electrically connected to the ground electrode (433).

[0213] The sensing voltage can be applied to the upper electrode (410), the shield electrode (420), the first lower electrode (431), and the second lower electrode (435) through the first pin (451), the second pin (452), the third pin (453), and the fourth pin (454), respectively. The ground electrode can be applied to the ground electrode (433) through the fifth pin (455). In this case, the shield electrode (420) can provide active shielding.

[0214] Alternatively, the second pin (452) may be omitted so that no voltage is applied to the shield electrode (420). In this case, the shield electrode (420) may provide passive shielding.

[0215] Referring again to FIGS. 19 to 21, the first and second pins (451, 452) may be positioned above the upper electrode (410), and the third to fifth pins (453, 454, 455) may be positioned below the shield electrode (420).

[0216] A portion of the first pin (451) may extend from the bottom (441) of the housing (440) toward the upper space of the upper electrode (410), and the remainder of the first pin (451) may extend in the opposite direction of the portion. The first pin (451) may be adjacent to the first protrusion (411a) of the upper electrode (410). The first coupling portion (411b) may protrude from the first protrusion (411a) and contact and couple to the first pin (451). The first coupling portion (411b) may be bent from the first protrusion (411a) to surround a portion of the first pin (451) and may be welded to the first pin (451). That is, the upper electrode (410) may be suspended from the first pin (451).

[0217] A portion of the second pin (452) may extend from the bottom (441) of the housing (440) toward the upper space of the upper electrode (410), and the remainder of the second pin (452) may extend in the opposite direction of the portion. The second pin (452) may be adjacent to the first protrusion (421a) of the shield electrode (420). The first coupling portion (421b) may protrude from the first protrusion (421a) and contact and couple to the second pin (452). The first coupling portion (421b) may be bent from the first protrusion (421a) to surround a portion of the second pin (452) and may be welded to the second pin (452). That is, the shield electrode (420) may be suspended from the second pin (452).

[0218] A portion of the third pin (453) may extend from the bottom (441) of the housing (440) toward the lower space of the shield electrode (420), and the remainder of the third pin (453) may extend in the opposite direction of the portion. The third pin (453) may be adjacent to the first lower electrode (431). The first coupling portion (4311b) may protrude from the first protrusion (4311a) and may contact and be coupled to the third pin (453). The first coupling portion (4311b) may be bent from the first protrusion (4311a) to surround a portion of the third pin (453) and may be welded to the third pin (453). That is, the first lower electrode (431) may be suspended from the third pin (453).

[0219] A portion of the fourth pin (454) may extend from the bottom (441) of the housing (440) toward the lower space of the shield electrode (420), and the remainder of the fourth pin (454) may extend in the opposite direction of the portion. The fourth pin (454) may be adjacent to the second lower electrode (435). The first coupling portion (4351b) may protrude from the first protrusion (4351a) and may contact and be coupled to the fourth pin (454). The first coupling portion (4351b) may be bent from the first protrusion (4351a) to surround a portion of the fourth pin (454) and may be welded to the fourth pin (454). That is, the second lower electrode (435) may be suspended from the fourth pin (454).

[0220] A portion of the fifth pin (455) may extend from the bottom (441) of the housing (440) toward the lower space of the shield electrode (420), and the remainder of the fifth pin (455) may extend in the opposite direction of the portion. The fifth pin (455) may be adjacent to the ground electrode (433). The first coupling portion (4331b) may protrude from the first protrusion (4331a) and may contact and be coupled to the fifth pin (455). The first coupling portion (4331b) may be bent from the first protrusion (4331a) to surround a portion of the fifth pin (455) and may be welded to the fifth pin (455). That is, the ground electrode (433) may be suspended from the fifth pin (455).

[0221] The first holder (461) may be disposed between the bottom (441) of the housing (440) and the electrode assembly (310). The first holder (461) may include an electrically insulating material such as plastic. For example, the first holder (461) may be PPS (Polyphenylene Sulfide). At least some of the plurality of pins (451, 452, 453, 454, 455) may penetrate the first holder (461). For example, the third to fifth pins (453, 454, 455) may penetrate the first holder (461). Accordingly, the first holder (461) may minimize movement of the pin assembly (450). The first holder (461) may be referred to as a pin fixing portion (461) or a first electrode fixing portion (461).

[0222] The second holder (462) may be positioned opposite the first holder (461) with respect to the electrode assembly (310). The second holder (462) may include an electrically insulating material such as plastic. For example, the second holder (462) may be PPS (Polyphenylene Sulfide). At least some of the plurality of electrodes (410, 420, 431, 433, 435) may be inserted into the second holder (462). All of the plurality of electrodes (410, 420, 431, 433, 435) may be inserted into the second holder (461). Accordingly, the second holder (462) may minimize movement of the electrode assembly (310). The second holder (462) may be referred to as a second electrode fixing part (462).

[0223] Referring again to FIG. 22, the pin assembly (450) can penetrate the bottom (441) of the housing (440), and the electrode assembly (310) can be coupled to the pin assembly (450). The electrode assembly (310) can be positioned inside the edge of the housing (440). The electrode assembly (310) can be positioned inside a circle formed by the side wall (442) of the housing (440). Accordingly, during the process of welding the housing (440) to the compressor (1, see FIG. 18), a short circuit of the sensor module (400S) can be prevented. In addition, the increase in the size of the sensor module (400S) can be minimized by limiting the width (diameter) of the sensor module (400S) to the width (diameter) of the housing (440).

[0224] The first lower electrode (431), the second lower electrode (435), and the ground electrode (433) of the lower electrode assembly (430) of FIG. 22 may be spaced apart from the shield electrode (420) by a predetermined distance (d) downward. In the horizontal direction, the distance (ds1) between the first lower electrode (431) and the ground electrode (433) may be different from the distance (ds2) between the second lower electrode (435) and the ground electrode (433). The distance (ds1) may be smaller than the distance (ds2). The width of the first lower electrode (431) (see height (h3) of FIG. 12), the width of the second lower electrode (435) (see height (h5) of FIG. 12), and the width of the ground electrode (433) (see height (h4) of FIG. 12) may correspond to each other. Here, in the vertical direction, the length of the lower electrode assembly (430) may be referred to as the width or height (see h3, h4, h5 of FIG. 12). The shape and arrangement of the lower electrode assembly (430) of FIG. 22 may correspond to the shape and arrangement of the lower electrode assemblies (431, 433, 435) described above with reference to FIG. 12.

[0225] FIGS. 24 to 27 are drawings illustrating a sensing module of a sensor according to one embodiment of the present disclosure.

[0226] Referring to FIGS. 24 to 27, the sensor (300) may include a sensing module (400S). The shape and arrangement of the lower electrode assembly (430) of the sensing module (400S) of FIGS. 24 to 27 may be different from the shape and arrangement of the lower electrode assembly (430) of the sensing module (400S) of FIGS. 18 to 23. The housing (440), pin assembly (450), upper electrode (410), and shield electrode (420) of the sensing module (400S) of FIGS. 24 to 27 may be the same as the housing (440), pin assembly (450), upper electrode (410), and shield electrode (420) of the sensing module (400S) of FIGS. 18 to 23.

[0227] The first lower electrode (431), the second lower electrode (435), and the ground electrode (433) of the lower electrode assembly (430) of FIG. 27 may be spaced apart from the shield electrode (420) by a predetermined distance (d) downward. In the horizontal direction, the distance (ds) between the first lower electrode (431) and the ground electrode (433) may correspond to the distance (ds) between the second lower electrode (435) and the ground electrode (433). The width of the first lower electrode (431) (see the height (h3) of the drawing reference numeral 1102 of FIG. 11) and the width of the ground electrode (433) (see the height (h4) of the drawing reference numeral 1102 of FIG. 11) may correspond to each other. The width of the second lower electrode (435) (see the height (h5) of the reference numeral 1102 of FIG. 11) may be smaller than the width of the ground electrode (433) (see the height (h4) of the reference numeral 1102 of FIG. 11). Here, in the vertical direction, the length of the lower electrode assembly (430) may be referred to as the width or the height (see h3, h4, h5 of the reference numeral 1102 of FIG. 11). The shape and arrangement of the lower electrode assembly (430) of FIG. 27 may correspond to the shape and arrangement of the lower electrode assemblies (431, 433, 435) described above with reference to FIG. 6A or the reference numeral 1102 of FIG. 11.

[0228] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 18 to 27 may be changed to the lower electrode assembly (431, 433, 435) of the reference numeral 1402 of FIG. 14, the lower electrode assembly (431, 433, 435) of the reference numeral 1602 of FIG. 16, or the lower electrode assembly (431, 433, 435) of the reference numeral 1702 of FIG. 17. At this time, the pin assembly (450) may have five pins and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431, 433, 435). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be four.

[0229] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 18 to 27 may be changed to the lower electrode assembly (431, 433) of FIG. 5A. At this time, the number of pins of the pin assembly (450) may be four, and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431, 433). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be three.

[0230] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 18 to 27 may be changed to the lower electrode assembly (431, 435) of the reference numeral 1101 of FIG. 11, the lower electrode assembly (431, 435) of the reference numeral 1401 of FIG. 14, the lower electrode assembly (431, 435) of the reference numeral 1601 of FIG. 16, or the lower electrode assembly (431, 435) of the reference numeral 1701 of FIG. 17. At this time, the number of pins of the pin assembly (450) may be four, and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431, 435). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be three.

[0231] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 18 to 27 may be changed to the lower electrode assembly (431) of FIG. 4A. At this time, the number of pins of the pin assembly (450) may be three, and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be two.

[0232] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 18 to 27 may be changed to the lower electrode assembly (431, 435) and the sub-shield electrode (425) of the drawing reference numeral 1502 of FIG. 15. At this time, the number of pins of the pin assembly (450) may be 5, and may be electrically connected to the upper electrode (410), the shield electrode (420), the lower electrode assembly (431, 435), and the sub-shield electrode (425). Alternatively, the pins connected to the shield electrode (420) or the sub-shield electrode (425) may be omitted, in which case the number of pins of the pin assembly (450) may be 4. Alternatively, the pins connected to the shield electrode (420) and the sub-shield electrode (425) may be omitted, in which case the number of pins of the pin assembly (450) may be three.

[0233] FIGS. 28 to 31 are drawings illustrating a sensing module of a sensor according to an embodiment of the present disclosure.

[0234] Referring to FIGS. 28 to 31, the sensor (300) may include a sensing module (400S). The shape and arrangement of the lower electrode assembly (430) of the sensing module (400S) of FIGS. 28 to 31 may be different from the shape and arrangement of the lower electrode assembly (430) of the sensing module (400S) of FIGS. 18 to 27. The housing (440), pin assembly (450), upper electrode (410), and shield electrode (420) of the sensing module (400S) of FIGS. 28 to 31 may be the same as the housing (440), pin assembly (450), upper electrode (410), and shield electrode (420) of the sensing module (400S) of FIGS. 18 to 27.

[0235] Referring to FIGS. 28 to 30, the lower electrode assembly (430) may be spaced downward from the shield electrode (420). The lower electrode assembly (430) may have a plate shape extending in a direction parallel to the shield electrode (420). The lower electrode assembly (430) may extend in a longitudinal direction of the shield electrode (420). Here, the longitudinal direction of the shield electrode (420) may be a direction parallel to long sides of the shield electrode (420). The electrodes of the lower electrode assembly (430) may be spaced apart from each other in the horizontal direction. The lower electrode assembly (430) may include a first lower electrode (431) and a second lower electrode (435).

[0236] The first lower electrode (431) may have a plate shape parallel to the shield electrode (420). The first lower electrode (431) may have an overall rectangular shape. The first lower electrode (431) may have two long sides that are opposite to each other and two short sides that are opposite to each other. An upper surface of the first lower electrode (431) may be adjacent to a lower surface of the shield electrode (420). The first protrusion (4311a) may protrude from the first short side (4311) of the first lower electrode (431) and may form one end of the first lower electrode (431). The second protrusion (4312a) may protrude from the second short side (4312) of the first lower electrode (431) and may form the other end of the first lower electrode (431). The portion of the first lower electrode (431) between the protrusions (4311a, 4312a) may be referred to as a first lower body (4310) and may have a length and width greater than the protrusions (4311a, 4312a). The length of the first lower body (4310) may be less than or equal to the length of the shield body (4200), and the shield body (4200) may cover the upper surface of the first lower body (4310).

[0237] The second lower electrode (435) may have a plate shape parallel to the shield electrode (420). The second lower electrode (435) may have an overall rectangular shape. The second lower electrode (435) may have two long sides that are opposite to each other and two short sides that are opposite to each other. The upper surface of the second lower electrode (435) may be adjacent to the lower surface of the shield electrode (420). The first protrusion (4351a) may protrude from the first short side (4351) of the second lower electrode (435) and may form one end of the second lower electrode (435). The second protrusion (4352a) may protrude from the second short side (4352) of the second lower electrode (435) and may form the other end of the second lower electrode (435). The portion of the second lower electrode (435) between the protrusions (4351a, 4352a) may be referred to as a second lower body (4350) and may have a length and width greater than the protrusions (4351a, 4352a). The length of the second lower body (4350) may be less than or equal to the length of the shield body (4200), and the shield body (4200) may cover the upper surface of the second lower body (4350).

[0238] Accordingly, the shield electrode (420) can be placed between the upper electrode (410) and the lower electrode assembly (430), and can shield the upper electrode (410) from the lower electrode assembly (430) while shielding the lower electrode assembly (430) from the upper electrode (410).

[0239] Referring to FIG. 31, the pin assembly (450) can penetrate the bottom (441) of the housing (440). The side wall (442) of the housing (440) can surround the pin assembly (450). A rib (441r) protruding from the inner surface of the bottom (441) can surround a portion of the outer surface of the pin assembly (450). A sealant (441s) can close a gap between the outer surface of the pin assembly (450) and the inner surface of the rib (441r). The sealant (441s) can be made of an electrical insulating material such as glass. The sealant (441s) can be referred to as an insulation material (441s) or a glass frit (441s).

[0240] The pin assembly (450) may include a plurality of pins. The pins may be electrically conductive. The number of pins may be equal to the number of electrodes of the electrode assembly (310). Alternatively, the number of pins may be one less than the number of electrodes of the electrode assembly (310). That is, the electrode assembly (310) may include pins connected to the upper electrode (410) and the lower electrode assembly (430), and may or may not include a pin connected to the shield electrode (420).

[0241] For example, the pin assembly (450) may include a first pin (451), a second pin (452), a third pin (453), and a fourth pin (454). The first to fourth pins (451, 452, 453, 454) may extend in a direction intersecting the bottom (441) of the housing (440). The first to fourth pins (451, 452, 453, 454) may be arranged adjacent to and along an edge of the bottom (441) of the housing (440). That is, the first to fourth pins (451, 452, 453, 454) may be arranged radially with respect to the center of the bottom (441) of the housing (440). The first pin (451) may be electrically connected to the upper electrode (410). The second pin (452) may be electrically connected to the shield electrode (420). The third pin (453) may be electrically connected to the first lower electrode (431). The fourth pin (454) may be electrically connected to the second lower electrode (435).

[0242] The sensing voltage can be applied to each of the upper electrode (410), the shield electrode (420), the first lower electrode (431), and the second lower electrode (435) through the first pin (451), the second pin (452), the third pin (453), and the fourth pin (454), respectively. At this time, the shield electrode (420) can provide active shielding.

[0243] Alternatively, the second pin (452) may be omitted so that no voltage is applied to the shield electrode (420). In this case, the shield electrode (420) may provide passive shielding.

[0244] Referring again to FIGS. 29 and 31, the first and second pins (451, 452) may be positioned above the upper electrode (410), and the third and fourth pins (453, 454) may be positioned below the shield electrode (420).

[0245] A portion of the first pin (451) may extend from the bottom (441) of the housing (440) toward the upper space of the upper electrode (410), and the remainder of the first pin (451) may extend in the opposite direction of the portion. The first pin (451) may be adjacent to the first protrusion (411a) of the upper electrode (410). The first coupling portion (411b) may protrude from the first protrusion (411a) and contact and couple to the first pin (451). The first coupling portion (411b) may be bent from the first protrusion (411a) to surround a portion of the first pin (451) and may be welded to the first pin (451). That is, the upper electrode (410) may be suspended from the first pin (451).

[0246] A portion of the second pin (452) may extend from the bottom (441) of the housing (440) toward the upper space of the upper electrode (410), and the remainder of the second pin (452) may extend in the opposite direction of the portion. The second pin (452) may be adjacent to the first protrusion (421a) of the shield electrode (420). The first coupling portion (421b) may protrude from the first protrusion (421a) and contact and couple to the second pin (452). The first coupling portion (421b) may be bent from the first protrusion (421a) to surround a portion of the second pin (452) and may be welded to the second pin (452). That is, the shield electrode (420) may be suspended from the second pin (452).

[0247] A portion of the third pin (453) may extend from the bottom (441) of the housing (440) toward the lower space of the shield electrode (420), and the remainder of the third pin (453) may extend in the opposite direction of the portion. The third pin (453) may be adjacent to the first lower electrode (431). The first connecting portion (4311b) may be at least a portion of the first protrusion (4311a). The first connecting portion (4311b) may be welded to a portion of the third pin (453). Alternatively, the first connecting portion (4311b) may be bent like the first connecting portion (411b) and welded to a portion of the third pin (453). That is, the first lower electrode (431) may be suspended from the third pin (453).

[0248] A portion of the fourth pin (454) may extend from the bottom (441) of the housing (440) toward the lower space of the shield electrode (420), and the remainder of the fourth pin (454) may extend in the opposite direction of the portion. The fourth pin (454) may be adjacent to the second lower electrode (435). The first connecting portion (4351b) may be at least a portion of the first protrusion (4351a). The first connecting portion (4351b) may be welded to a portion of the fourth pin (454). Alternatively, the first connecting portion (4351b) may be bent like the first connecting portion (421b) and welded to a portion of the fourth pin (454). That is, the second lower electrode (435) may be suspended from the fourth pin (454).

[0249] The first holder (461) may be positioned between the bottom (441) of the housing (440) and the electrode assembly (310). The first holder (461) may include an electrically insulating material such as plastic. For example, the first holder (461) may be PPS (Polyphenylene Sulfide). At least some of the plurality of pins (451, 452, 453, 454) may penetrate the first holder (461). For example, the third and fourth pins (453, 454) may penetrate the first holder (461). Accordingly, the first holder (461) may minimize movement of the pin assembly (450).

[0250] The second holder (462) may be positioned opposite the first holder (461) with respect to the electrode assembly (310). The second holder (462) may include an electrically insulating material such as plastic. For example, the second holder (462) may be PPS (Polyphenylene Sulfide). At least some of the plurality of electrodes (410, 420, 431, 435) may be inserted into the second holder (462). All of the plurality of electrodes (410, 420, 431, 435) may be inserted into the second holder (461). Accordingly, the second holder (462) may minimize movement of the electrode assembly (310).

[0251] Referring again to FIG. 31, the pin assembly (450) can penetrate the bottom (441) of the housing (440), and the electrode assembly (310) can be coupled to the pin assembly (450). The electrode assembly (310) can be positioned inside an edge of the housing (440). The electrode assembly (310) can be positioned inside a circle formed by the side walls (442) of the housing (440).

[0252] The first lower electrode (431) and the second lower electrode (435) of the lower electrode assembly (430) of FIG. 31 may be spaced apart from the shield electrode (420) by a certain distance (d) downward. The shape and arrangement of the lower electrode assembly (430) of FIG. 31 may correspond to the shape and arrangement of the lower electrode assemblies (431, 435) described above with reference to the drawing reference numeral 1001 of FIG. 10.

[0253] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 28 to 31 may be changed to the lower electrode assembly (431, 435) of the reference numeral 1301 of FIG. 13. At this time, the number of pins of the pin assembly (450) may be four, and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431, 435). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be three.

[0254] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 28 to 31 may be changed to the lower electrode assembly (431) of FIG. 4B. At this time, the number of pins of the pin assembly (450) may be three, and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be two.

[0255] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 28 to 31 may be changed to the lower electrode assembly (431, 433) of FIG. 5B. At this time, the number of pins of the pin assembly (450) may be four, and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431, 433). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be three.

[0256] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 28 to 31 may be changed to the lower electrode assembly (431, 433, 435) of the drawing reference numeral 1002 of FIGS. 6b and 10, the lower electrode assembly (431, 433, 435) of the drawing reference numeral 1003 of FIG. 10, or the lower electrode assembly (431, 433, 435) of the drawing reference numeral 1302 of FIG. 13. At this time, the number of pins of the pin assembly (450) may be 5, and may be electrically connected to the upper electrode (410), the shield electrode (420), and the lower electrode assembly (431, 433, 435). Alternatively, the pin connected to the shield electrode (420) may be omitted, in which case the number of pins of the pin assembly (450) may be four.

[0257] Meanwhile, the lower electrode assembly (430) of the sensing module (400S) of FIGS. 28 to 31 may be changed to the lower electrode assembly (431, 435) and the sub-shield electrode (425) of the drawing reference numeral 1501 of FIG. 15. At this time, the number of pins of the pin assembly (450) may be 5, and may be electrically connected to the upper electrode (410), the shield electrode (420), the lower electrode assembly (431, 435), and the sub-shield electrode (425). Alternatively, the pins connected to the shield electrode (420) or the sub-shield electrode (425) may be omitted, in which case the number of pins of the pin assembly (450) may be 4. Alternatively, the pins connected to the shield electrode (420) and the sub-shield electrode (425) may be omitted, in which case the number of pins of the pin assembly (450) may be three.

[0258]

[0259] As described above, according to at least one embodiment of the present disclosure, the concentration of oil present inside the compressor (1) can be accurately detected.

[0260] Additionally, according to at least one embodiment of the present disclosure, the height of the oil surface can be accurately detected based on the concentration of oil present inside the compressor.

[0261] Additionally, according to at least one embodiment of the present disclosure, the amount of oil present inside the compressor can be accurately detected.

[0262] Additionally, according to at least one embodiment of the present disclosure, a sensor optimized to detect the concentration of oil, the height of the oil surface, and the amount of oil together using a plurality of electrodes can be provided.

[0263] Additionally, according to at least one embodiment of the present disclosure, the detection range for the height of the surface of the oil may not be limited by the size of the electrode by using the self-capacitance method.

[0264] Additionally, various examples of the sensing module of the sensor can be provided.

[0265]

[0266] Referring to FIGS. 1 to 31, a sensor according to one aspect of the present disclosure may include: a cap; electrodes facing the cap and spaced apart from each other; and pins penetrating the cap and electrically connected to the electrodes, wherein the electrodes may include: an upper electrode in the shape of a horizontal plate; a lower electrode positioned below the upper electrode; and a shield electrode positioned between the upper electrode and the lower electrode.

[0267] The pins may include: a first pin connected to the upper electrode; a second pin connected to the shield electrode; and a third pin connected to the lower electrode.

[0268] The above second pin may be omitted.

[0269] The above pins may be arranged radially with respect to the center of the cap.

[0270] The upper electrode, the lower electrode, and the shield electrode may be positioned on the inside of the edge of the cap.

[0271] Each of the upper electrode, the lower electrode, and the shield electrode may include a connecting portion that protrudes from each of the upper electrode, the lower electrode, and the shield electrode and contacts and connects to each of the pins.

[0272] The upper electrode may include: a joint that is bent from the upper electrode and wraps around a pin connected to the upper electrode, and is welded to the pin connected to the upper electrode.

[0273] Each of the upper electrode, the lower electrode and the shield electrode may include: one end adjacent to the cap; and an opposite end opposite to the one end, wherein the one end may be suspended from the pin.

[0274] The above sensor may further include a holder to which the other ends of each of the upper electrode, the lower electrode, and the shield electrode are coupled.

[0275] The above shield electrode may have the shape of a horizontal plate and may cover the lower surface of the upper electrode.

[0276] The lower electrode may have the shape of a horizontal plate or the shape of a vertical plate, and the shield electrode may cover the upper surface or upper edge of the lower electrode.

[0277] The shield electrode may be arranged parallel to the upper electrode, and the lower electrode may be arranged parallel to the shield electrode or in a direction crossing the shield electrode.

[0278] The lower electrode may include: a first lower electrode; and a second lower electrode spaced apart from the first lower electrode.

[0279] The sensor may further include a ground electrode disposed between the first lower electrode and the second lower electrode.

[0280] The above sensor may further include a ground electrode replacing the second lower electrode.

[0281]

[0282] The attached drawings are only intended to facilitate understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present disclosure.

[0283] Meanwhile, the operating method of the present disclosure can be implemented as processor-readable code on a processor-readable recording medium. A processor-readable recording medium includes all types of recording devices that store data that can be read by a processor. Examples of processor-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage devices, etc., and also include those implemented in the form of a carrier wave, such as transmission via the Internet. Furthermore, the processor-readable recording medium can be distributed across network-connected computer systems, so that the processor-readable code can be stored and executed in a distributed manner.

[0284] In addition, although the preferred embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above, and various modifications may be made by a person having ordinary skill in the art to which the present invention pertains without departing from the gist of the present disclosure as claimed in the claims, and such modifications should not be understood individually from the technical idea or prospect of the present disclosure.

Claims

1. Cap; Electrodes facing the cap and spaced apart from each other; and comprising pins penetrating the cap and electrically connected to the electrodes; The above electrodes are: Upper electrode in the shape of a horizontal plate; A lower electrode positioned below the upper electrode; and, A sensor comprising a shield electrode disposed between the upper electrode and the lower electrode.

2. In paragraph 1, The above pins are: A first pin connected to the upper electrode; a second pin connected to the above shield electrode; and, A sensor comprising a third pin connected to the lower electrode.

3. In paragraph 2, The sensor in which the second pin is omitted.

4. In paragraph 1, The above pins are, Sensors arranged radially with respect to the center of the above cap.

5. In paragraph 1, The upper electrode, the lower electrode and the shield electrode, A sensor placed on the inside of the edge of the above cap.

6. In paragraph 1, Each of the upper electrode, the lower electrode and the shield electrode: A sensor including a connecting portion protruding from each of the upper electrode, the lower electrode, and the shield electrode and contacting and connecting to each of the pins.

7. In paragraph 1, The upper electrode is: A sensor including a joint that is bent from the upper electrode and wraps around a pin connected to the upper electrode, and is welded to the pin connected to the upper electrode.

8. In paragraph 1, Each of the upper electrode, the lower electrode and the shield electrode: one end adjacent to the above cap; and, Including the other end opposite to the above, The above one is a sensor hanging on the pin.

9. In paragraph 8, A sensor further comprising a holder to which the other ends of each of the upper electrode, the lower electrode, and the shield electrode are connected.

10. In paragraph 1, The above shield electrode is, A sensor having the shape of a horizontal plate and covering the lower surface of the upper electrode.

11. In paragraph 1, The above lower electrode is, Having the shape of a horizontal plate or the shape of a vertical plate, The above shield electrode is, A sensor covering the upper surface or upper edge of the lower electrode.

12. In paragraph 1, The above shield electrode is, It is arranged parallel to the upper electrode, The above lower electrode is, A sensor arranged parallel to the shield electrode or arranged in a direction crossing the shield electrode.

13. In paragraph 1, The above lower electrode: First lower electrode; and, A sensor comprising a second lower electrode spaced apart from the first lower electrode.

14. In paragraph 13, A sensor further comprising a ground electrode disposed between the first lower electrode and the second lower electrode.

15. In paragraph 13, A sensor further comprising a ground electrode replacing the second lower electrode.

Images