KR20210087801A - Motor operated compressor - Google Patents

Abstract

An embodiment of the present invention provides a motor-driven compressor, wherein the length of a pressure-reducing flow path can vary according to a difference in pressures. As a difference in pressures increases, the length of the pressure-reducing flow path gets longer to increase the resistance length of the pressure-reducing flow path. Accordingly, an increase in an amount of oil supplied per unit time, which is caused by the difference in pressures, is offset by a decrease in an amount of oil supplied per unit time, which is caused by an increase in the resistance length of the pressure-reducing flow path. Meanwhile, when a difference in pressures decreases, the length of the pressure-reducing flow path gets shorter to decrease the resistance length of the pressure-reducing flow path. Accordingly, a decrease in an amount of oil supplied per unit time, which is caused by a decrease in the difference in pressures, is compensated by an increase in an amount of oil supplied per unit time, which is caused by a decrease in the resistance length of the pressure-reducing flow path. That is, an embodiment of the present invention provides a motor-driven compressor in such a structure that a deviation in an amount of oil supplied per unit time, which is caused by a difference in pressures, can be reduced.

Description

Electric Compressor {MOTOR OPERATED COMPRESSOR}

The present invention relates to an electric compressor, and more particularly, to an electric compressor having a structure in which an oil supply amount of oil can be adjusted.

The compressor is divided into a mechanical compressor using an engine as a driving source and an electric compressor using a motor as a driving source. As an electric compressor, a scroll compression method suitable for operation with a high compression ratio is widely known.

An electric compressor having a scroll compression method (hereinafter, abbreviated as an electric compressor) is provided with an electric part composed of a driving motor inside a sealed casing. And a compression part composed of a fixed scroll and an orbiting scroll is installed on one side of the electric part.

The electric part and the compression part are connected by a rotating shaft. The rotational force of the electric part is transmitted to the compression part through the rotation shaft. And the compression unit compresses the refrigerant by the rotational force transmitted through the rotating shaft.

An oil separation chamber for separating oil from the compressed and discharged refrigerant is formed in the electric compressor. The refrigerant separated from the oil in the oil separation chamber is discharged to the exhaust port, and the oil separated from the refrigerant is accommodated in the oil separation chamber.

The oil may be supplied to a back pressure chamber supporting the compression unit and/or an intermediate pressure chamber formed in the compression unit.

Since a pressure difference is generated between the oil separation chamber and the back pressure chamber (or intermediate pressure chamber) during the operation of the electric compressor, the electric compressor is provided with a pressure reducing device for depressurizing the oil passing between the oil separation chamber and the back pressure chamber (or intermediate pressure chamber). The oil in the oil separation chamber is decompressed through a pressure reducing device and then supplied to the back pressure chamber (or intermediate pressure chamber).

If the oil is not smoothly supplied, abrasion between the bearing surfaces or the scrolls may occur, thereby reducing reliability. Therefore, the oil supply amount should be maintained larger than the minimum oil supply amount that can ensure the reliability of the electric compressor.

The minimum oil supply amount may vary depending on the number of revolutions at which the electric compressor is operated. A relatively small amount of minimum oil supply is required when operating in a low rotational condition, and a relatively large amount of minimum oil supply is required when operating in a high rotational condition.

Since the electric compressor operates at various rotations from low to high rotation, the minimum oil supply is designed for high rotation conditions.

As the electric compressor operates, the pressure difference between the oil separation chamber and the back pressure chamber (or intermediate pressure chamber) increases, and when the pressure difference increases, the amount of oil supplied increases. That is, an excessive amount of oil may be supplied than the amount of oil required for reliability of the electric compressor.

However, when the supply amount of oil is excessively increased, the amount of oil introduced into the compression chamber is increased, which may cause a problem in that compression loss occurs. In addition, there may be a problem that the oil is not sufficiently filtered in the oil separation chamber and is discharged together with the refrigerant.

In addition, when the amount of oil supplied from the oil separation chamber to the back pressure chamber (or intermediate pressure chamber) is increased compared to the amount of oil flowing into the oil separation chamber, the supply of oil is momentarily stopped, thereby reducing the reliability of the electric compressor . In consideration of this problem, an oil separation chamber having a capacity greater than the minimum oil supply amount is provided.

However, as the capacity of the oil separation chamber increases, the size of the electric compressor increases and the manufacturing cost of the compressor increases.

US Patent Document No. 77,044,723 discloses an electric compressor having a pressure reducing device.

However, in the electric compressor, when the pressure difference is increased, the oil supply amount of the oil is excessively increased, so that when the pressure difference is increased, excessive oil is supplied compared to the minimum oil supply amount. That is, the electric compressor does not suggest a method for optimizing the oil supply amount.

In addition, the size of the oil separation chamber is excessively large compared to the minimum oil supply amount. This may result in the overall size of the compressor being increased. That is, the electric compressor does not suggest a method for downsizing the compressor.

US Registered Patent Document No. 7,044,723 (2006. 05. 16.)

An object of the present invention is to provide an electric compressor having a structure capable of solving the above-described problems.

First, an object of the present invention is to provide an electric compressor having a structure capable of suppressing excessive supply of oil.

Another object of the present invention is to provide an electric compressor having a structure capable of reducing a difference in an oil supply amount according to a pressure difference.

Another object of the present invention is to provide an electric compressor having a structure in which a length of a reduced pressure passage can be changed according to a pressure difference.

Another object of the present invention is to provide an electric compressor having a structure in which a length of a reduced pressure passage increases as a pressure difference increases.

Another object of the present invention is to provide an electric compressor having a structure in which a length of a reduced pressure passage is reduced as a pressure difference is reduced.

Another object of the present invention is to provide an electric compressor having a structure in which the overall size can be reduced.

Another object of the present invention is to provide an electric compressor having a structure in which the movement distance of the pressure reducing pin can be limited.

Another object of the present invention is to provide an electric compressor having a structure in which the amount of impact applied to the decompression pin can be reduced in the process in which the decompression pin is converted from a moving state to a stop state.

Another object of the present invention is to provide an electric compressor having a structure in which noise that may be generated in a process in which the decompression pin is converted from a moving state to a stationary state can be reduced.

In order to achieve the above object, the present invention provides an electric compressor having the following structure.

First, the electric compressor according to the present invention includes a housing; a driving motor provided inside the housing; a compression unit operated by the driving motor to compress the refrigerant; an oil separation chamber provided at one side of the compression unit to separate oil from the refrigerant discharged from the compression unit; a back pressure chamber provided on the one side or the other side opposite to the one side of the compression unit to support the compression unit; a communication passage connecting the oil separation chamber and the back pressure chamber; and a pressure reducing unit provided in the communication passage to reduce the pressure of the fluid moving from the oil separation chamber to the back pressure chamber.

In addition, the pressure reducing unit may include a pressure reducing pin inserted into the communication passage by a predetermined length;

and an elastic member positioned on one side of the pressure reducing pin toward the back pressure chamber to press the pressure reducing pin, the predetermined length being greater than or equal to a predetermined first length and less than or equal to a predetermined second length, and a portion of the pressure reduction pin Between the portion inserted into the communication passage and the communication passage, a pressure reduction passage through which the fluid moving from the oil separation chamber to the back pressure chamber is decompressed is formed.

In addition, as the pressure difference between the oil separation chamber and the back pressure chamber increases, the predetermined length into which the pressure reducing pin is inserted increases.

In addition, as the pressure difference between the oil separation chamber and the back pressure chamber is reduced, the predetermined length into which the pressure reducing pin is inserted is reduced.

In addition, a support end protruding from an inner circumferential surface of the communication passage to support the elastic member is formed on one side of the elastic member facing the back pressure chamber.

In addition, the oil separation chamber is provided with a stopping member that is spaced apart from the inlet of the communication passage opened toward the oil separation chamber by a predetermined distance and partially overlaps the pressure reduction pin in the longitudinal direction of the pressure reduction pin.

In addition, a buffer member having an elastic force is provided on one side of the stopping member facing the pressure-reducing pin, and the buffer member partially overlaps the pressure-reducing pin and the pressure-reducing pin in a longitudinal direction.

In addition, the oil separation chamber is formed with a communication space open toward the oil separation chamber, the inlet of the communication passage opened toward the oil separation chamber is formed in the communication space, and the open portion of the communication space is connected to the filter member. and the filter member overlaps the pressure reduction pin in the longitudinal direction of the pressure reduction pin.

In addition, the electric compressor according to the present invention, the main housing; an electric part provided in the inner space of the main housing; a compression unit provided in the inner space of the main housing and driven by the electric unit to compress the refrigerant; a rear housing provided on the other side opposite to one side of the compression part facing the electric part and coupled to the main housing; an oil separation chamber formed in the rear housing and separating oil from the refrigerant discharged from the compression unit; a back pressure chamber formed between the rear housing and the compression unit and supporting the compression unit; a communication passage formed through the rear housing to communicate between the oil separation chamber and the back pressure chamber; and a pressure reducing unit provided in the communication passage to reduce the pressure of the fluid moving from the oil separation chamber to the back pressure chamber.

In addition, the pressure reducing unit may include a pressure reducing pin inserted into the communication passage by a predetermined length; and an elastic member positioned at one side of the pressure reducing pin toward the back pressure chamber to press the pressure reducing pin.

In addition, the predetermined length is equal to or greater than a preset first value and less than or equal to a preset second value.

In addition, a pressure reducing passage through which the fluid moving from the oil separation chamber to the back pressure chamber is decompressed is formed between a portion of the pressure reducing pin inserted into the communication passage and the communication passage.

In addition, as the pressure difference between the oil separation chamber and the back pressure chamber increases, the predetermined length into which the pressure reducing pin is inserted increases.

In addition, as the pressure difference between the oil separation chamber and the back pressure chamber is reduced, the predetermined length into which the pressure reducing pin is inserted is reduced.

In addition, a support end protruding from an inner circumferential surface of the communication passage to support the elastic member is formed on one side of the elastic member facing the back pressure chamber.

In addition, a communication space having a larger diameter than that of the communication passage is recessed in the oil separation chamber, and an inlet of the communication passage toward the oil separation chamber communicates with the communication space.

In addition, a stopping member adjacent to the communication space is coupled to one side of the oil separation chamber on which the communication space is formed, and the stopping member is spaced apart from the inlet of the communication passage by a predetermined distance, and the pressure reducing pin in the longitudinal direction to partially overlap the pressure reducing pin.

In addition, a buffer member having an elastic force is provided on one side of the stopping member facing the pressure-reducing pin, and the buffer member partially overlaps the pressure-reducing pin and the pressure-reducing pin in a longitudinal direction.

In addition, a filter member covering the communication space is coupled to one side of the oil separation chamber on which the communication space is formed, and the filter member overlaps the pressure reducing pin and the pressure reducing pin in a longitudinal direction.

According to the present invention, the following effects can be achieved.

First, when the pressure difference between the oil separation chamber and the back pressure chamber is increased, the length of the communication passage may be increased, so that the resistance length of the communication passage may be increased.

Thereby, an increase in the oil supply amount per unit time due to an increase in the pressure difference is attenuated by a decrease in the oil supply amount per unit time due to an increase in the resistance length.

As a result, it can be suppressed from excessively increasing the supply amount of oil due to an increase in the pressure difference.

As a result, supply of an excessive amount of oil to the compression chamber is suppressed, and thus the volume of the refrigerant supplied into the compression chamber can be increased, thereby improving the compression efficiency.

Furthermore, it can be suppressed that excessive oil is supplied to the oil separator, so that oil is not separated from the oil separator and discharged together with the refrigerant.

In addition, when the pressure difference between the oil separation chamber and the back pressure chamber is reduced, the length of the communication passage may be reduced, so that the resistance length of the communication passage may be reduced.

Thereby, a decrease in the oil supply amount per unit time due to a decrease in the pressure difference is compensated for by an increase in the oil supply amount per unit time due to a decrease in the resistance length.

As a result, when the pressure difference is reduced, excessive reduction of the oil supply amount per unit time can be suppressed, so that it is possible to suppress fluctuations in the oil supply amount per unit time due to the increase or decrease of the pressure difference. That is, the difference in the oil supply amount generated by the pressure difference between the oil separation chamber and the back pressure chamber may be reduced.

Thereby, since the supply amount of oil per unit time can be designed as the minimum supply amount for securing the reliability of the electric compressor, the design capacity of the oil separator and the oil separation chamber can be miniaturized.

Furthermore, the electric compressor can be miniaturized, and the cost required for manufacturing the electric compressor can be reduced.

In addition, a stopping member for limiting the length at which the pressure reducing pin can protrude from the communication passage is provided. Thereby, it is possible to prevent the pressure reducing pin from being separated from the communication passage.

In addition, a buffer member may be provided on the stop member. Thereby, the amount of impact applied to the pressure-reducing pin is alleviated, and the reliability of the pressure-reducing pin can be improved. Furthermore, noise generation due to the collision of the pressure reducing pin can be reduced.

In addition, the collision between the pressure reducing pin and the stopping member can be prevented by the buffer member. Thereby, the reliability of the pressure reducing pin can be improved and noise generation due to the collision of the pressure reducing pin can be prevented.

In addition, the stop member may be provided with a filter member. Accordingly, it is possible to prevent the decompression pin from being separated from the communication passage, and at the same time, it is possible to suppress the introduction of foreign substances into the pressure reduction passage. As a result, the occurrence of wear, refrigerant leakage, and friction loss that may be caused by foreign matter can be suppressed.

1 is a perspective view showing an electric compressor according to the present invention.
FIG. 2 is an exploded perspective view illustrating the electric compressor of FIG. 1 .
FIG. 3 is a cross-sectional view illustrating the electric compressor of FIG. 1 .
FIG. 4 is a partial perspective view illustrating the decompression unit of FIG. 1 .
FIG. 5 is a cross-sectional view showing the pressure reducing unit of FIG. 1 .
FIG. 6 is a cross-sectional view showing the pressure-reducing unit of FIG. 1 .
7 is a partial perspective view illustrating another embodiment of the decompression unit of FIG. 1 .
FIG. 8 is a cross-sectional view showing the decompression unit of FIG. 7 .
FIG. 9 is a cross-sectional view showing the decompression unit of FIG. 7 .
FIG. 10 is a cross-sectional view illustrating a modified example of the decompression unit of FIG. 7 .
FIG. 11 is a cross-sectional view showing the decompression unit of FIG. 10 .
FIG. 12 is a cross-sectional view illustrating another modified example of the decompression unit of FIG. 7 .
FIG. 13 is a cross-sectional view illustrating the decompression unit of FIG. 12 .
14 is a partial perspective view illustrating still another modified example of the decompression unit of FIG. 7 .
FIG. 15 is a cross-sectional view showing the decompression unit of FIG. 14 .
FIG. 16 is a cross-sectional view showing the decompression unit of FIG. 14 .

Hereinafter, an electric compressor according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the following description, in order to clarify the characteristics of the present invention, descriptions of some components may be omitted.

1 is a perspective view showing an external appearance of an electric compressor according to the present invention.

Referring to FIG. 1 , the electric compressor 100 according to the present embodiment includes a compression module 101 and an inverter module 102 . The compression module 101 refers to a set of components for compressing a fluid such as a refrigerant, and the inverter module 102 refers to a set of components for controlling the operation of the compression module 101 . The inverter module 102 may be coupled to the front side of the compression module 101 . Hereinafter, the side where the inverter module 102 is installed is defined as the front side, and the side where the compression module 101 is installed is defined as the rear side, respectively.

The compression target fluid (hereinafter, referred to as a refrigerant) flows into the compressor 100 through the intake port 111 , and is discharged to the outside of the compressor 100 through the exhaust port 125 . Accordingly, it is advantageous for the inverter module 102 to be disposed on the front side close to the intake port 111 to cool the inverter module 102 .

The external appearance of the compression module 101 may be formed by the main housing 110 constituting the first housing and the rear housing 120 constituting the second housing. For example, the main housing 110 has a closed front end and an open rear end, and the rear housing 120 has an open front end and a closed rear end. Accordingly, the rear end of the main housing 110 and the front end of the rear housing 120 may communicate with each other to form a sealed casing of the compression module 101 .

FIG. 2 is an exploded perspective view of the electric compressor according to FIG. 1 , and FIG. 3 is a cross-sectional view showing the inside of the electric compressor according to FIG. 2 assembled.

Referring to FIGS. 2 and 3 , the main housing 110 has a hollow cylindrical shape, a polygonal cylinder shape, or an external shape corresponding thereto. The main housing 110 may be arranged to extend in the lateral direction. The main housing 110 is formed to surround the electric part 130, which will be described later. One end in the axial direction of the main housing 110 may be formed in a closed shape and the other end in the axial direction may be opened.

An intake port 111 is formed on the outer peripheral surface of the main housing 110 . The intake port 111 forms a flow path for supplying a refrigerant (eg, R134a, R32, CO2, etc.) to the internal space of the compression module 101 .

The rear housing 120 is coupled to the rear end of the main housing 110 . The rear housing 120 may be formed to cover the rear end of the main housing 110 . An exhaust port 125 may be formed in the rear housing 120 , and an oil separator 123a may be installed in the exhaust port 125 .

In addition, the rear housing 120 is provided to face the rear surface of the orbiting scroll 150, which will be described later, and includes a plate support part 121, an intermediate pressure space part 122, a discharge pressure space part 123, and an oil separation space part ( 124), which will be described later.

Next, the compression module 101 will be described.

Referring back to FIGS. 2 and 3 , the compression module 101 has an electric part (driver or drive motor) 130 and a compression part 105 in the inner space of the main housing 110 forming a part of the casing in the axial direction. is arranged, and the transmission unit 130 and the compression unit 105 are connected by a rotation shaft 135 . The electric part 130 is positioned on the front side of the main housing 110 , and the compression part 105 is positioned on the rear side of the main housing 110 , respectively.

Here, as the intake port 111 is formed in the main housing 110 , the inner space of the main housing 110 forms a suction space S1 , and the electric unit 130 and the compression unit 105 increase the suction pressure. It is disposed in the suction space (S1) to form. The suction space S1 may also be referred to as a motor room.

The electric part 130 is formed to generate a driving force for pivoting the orbiting scroll 150 of the compression part 105 . The electric part 130 is also referred to as a driving motor, and is composed of an electric motor.

The electric part 130 includes a stator 131 and a rotor 132 .

The stator 131 is inserted and fixed to the inner circumferential surface of the main housing 110 by shrink fit (or hot press fit). However, it may be fixed by welding after insertion or by using another fixing member.

The rotor 132 is rotatably disposed inside the stator 131 . When electric power is applied to the stator 131 , the rotor 132 rotates by electromagnetic interaction with the stator 131 .

A rotation shaft 135 is coupled to the center of the rotor 132 . An eccentric portion 135c is formed on the rotating shaft 135 and is eccentrically coupled to the orbiting scroll 150 . Accordingly, the rotating shaft 135 transmits the rotational force of the driving motor to the orbiting scroll 150 . The rotation shaft will be described again later.

Next, the compression unit will be described. 4 is a plan view showing the coupling state of the fixed scroll and the orbiting scroll in the compression unit according to the present invention.

The compression unit 105 includes a fixed scroll 140 and an orbiting scroll 150 . The fixed scroll 140 may be defined as a first scroll, and the orbiting scroll 150 may be defined as a second scroll, respectively. Also, the fixed scroll 140 may be referred to as a frame scroll. The frame scroll is a mixed member of the frame and the fixed scroll, and performs both the role of the frame supporting the rotation shaft and the role of the fixed scroll forming the compression chamber. Accordingly, hereinafter, fixed scroll is a name that encompasses frame scroll.

The fixed scroll 140 and the orbiting scroll 150 are coupled to each other to form a pair of compression chambers (V). As the orbiting scroll 150 orbits, the volume of the compression chamber is repeatedly changed, and accordingly, the refrigerant is compressed in the compression chamber (V).

The fixed scroll 140 is disposed relatively close to the transmission unit 130 , and the orbiting scroll 150 is disposed relatively far from the transmission unit 130 . The fixed scroll 140 is disposed between the orbiting scroll 150 and the main housing 110 in the axial direction. The orbiting scroll 150 is disposed between the fixed scroll 140 and the rear housing 120 in the axial direction.

Referring to FIG. 3 , the fixed scroll 140 according to the present embodiment includes a fixed head plate portion 141 , a side wall portion 142 , and a fixed wrap 143 .

The fixed head plate part 141 is formed in a substantially disk shape. A suction port 145 for communicating between the suction space S1 and the suction chamber V1 is formed through the edge of the fixed head plate 141 . Accordingly, it is preferable that the scroll support surface 112 of the main housing 110, which will be described later, has a radial width of a degree that does not cover the suction port 145 .

A rotation shaft support protrusion 146 extending in the axial direction toward the transmission 130 is formed in the central portion of the fixed head plate 141 , and the rotation shaft accommodating part 147 passes through the rotation shaft support protrusion 146 in the axial direction. is formed Accordingly, the rotation shaft support protrusion 146 is formed in the shape of a bush.

The main bearing 171 is inserted and fixed to the inner circumferential surface of the rotating shaft accommodating part 147 so that the main bearing part 135a of the rotating shaft 135 is inserted and supported in the radial direction. The main bearing 171 may be formed of a ball bearing, but in this embodiment, a bush bearing is applied to reduce manufacturing cost for the compressor and reduce friction loss and vibration noise.

A sealing member (not shown) for sealing between the rotation shaft 135 and the fixed scroll 140 may be provided at the front end of the rotation shaft accommodating part 147 . Accordingly, in the rotation shaft 135 , the main bearing part 135a formed on the rear side with respect to the rotor 132 of the transmission part 130 is radially supported by the fixed scroll 140 .

Here, the sub bearing part 135b formed on the front side of the rotation shaft 135 may be supported by the sub bearing 172 provided on the front side surface of the main housing 110 . The sub bearing 172 is made of a ball bearing, and may be inserted into and coupled to the shaft support 113 provided on the front inner surface of the main housing 110 . As the sub-bearing 172 is made of a ball bearing, the rotating shaft 135 is radially and axially supported by the sub-bearing 172 .

Referring to FIG. 3 , the side wall portion 142 of the fixed scroll 140 according to the present embodiment extends in the axial direction by a predetermined height from the rear surface of the fixed head plate portion 141, and is formed in an annular shape along the circumferential direction. do.

Here, the fixed scroll 140 may be press-fitted to the inner circumferential surface of the main housing 110 and fixed, or may be fixed by being supported in both axial directions between the main housing 110 and the rear housing 120 .

The fixed wrap 143 is formed to protrude toward the orbiting scroll 150 from the rear surface of the fixed end plate 141 facing the orbiting scroll 150 . The fixed wrap 143 may be formed in an involute shape, but in this embodiment, the rotating shaft 135 penetrates the fixed scroll 140 and is inserted into the orbiting scroll 150 and coupled thereto. That is, the fixing wrap 143 according to the present embodiment may be formed in a non-involute shape.

Meanwhile, the orbiting scroll 150 according to the present embodiment is disposed at a position facing the fixed scroll 140 . The orbiting scroll 150 is coupled to the eccentric portion 135c provided at the rear end of the rotation shaft 135 . Accordingly, the orbiting scroll 150 is eccentrically coupled to the rotation shaft 135 . The orbiting scroll 150 receiving the rotational force through the eccentric portion 135c is rotated by the anti-rotation mechanism 160 .

Referring to FIG. 3 , the orbiting scroll 150 according to the present embodiment includes a turning head plate part 151 , a turning wrap 152 and a rotation shaft coupling part 153 .

The turning head plate part 151 is formed in a plate shape corresponding to the fixed head plate part 141 . If the fixed head plate part 141 has a disk-shaped cross section, the orbiting head plate part 151 has a disk-shaped cross-section.

A turning wrap 152 that engages with the fixed wrap 143 to form a compression chamber V is formed on the front surface facing the fixed scroll 140 among both sides of the turning end plate 151 in the axial direction.

The orbiting wrap 152 according to this embodiment protrudes in the shape of an involute curve, an arithmetic spiral (Archimedean spiral) or a logarithmic spiral (Logarithmic spiral) from the front surface of the turning head plate part 151 could be However, the orbiting wrap 152 according to the present embodiment may be formed in a non-involute shape together with the fixed wrap 143 . That is, the orbiting wrap 152 and the fixed wrap 143 may be formed as an atypical curve connecting a plurality of curves.

The rotating shaft coupling part 153 protrudes toward the fixed head plate part 141 from the center of the turning head plate part 151 . For example, the rotation shaft coupling part 153 may be formed at a position corresponding to a base circle defining the orbital wrap 152 . Accordingly, the rotation shaft coupling portion 153 forms the innermost portion of the orbital wrap 152 .

The rotation shaft coupling portion 153 is formed in a hollow cylindrical shape to accommodate the eccentric portion 135c of the rotation shaft 135 . The rotation shaft coupling portion 153 is formed to surround the eccentric portion 135c of the rotation shaft 135 .

The rotation shaft coupling portion 153 of the orbiting scroll 150 is opened only in one side. For example, the rotating shaft coupling portion 153 of the orbiting scroll 150 is opened toward the fixed head plate 141 , but the rear surface opposite to the opened portion is blocked by the orbiting head plate 151 . Accordingly, the eccentric portion 135c of the rotating shaft 135 is inserted into the rotating shaft coupling portion 153 of the orbiting scroll 150 , but does not penetrate the orbiting head plate portion 151 .

The rear surface of the rotation shaft coupling portion 153 is spaced apart from the end surface of the eccentric portion 135c of the rotation shaft 135 by a predetermined interval. Accordingly, a predetermined oil storage space S5 is formed on the rear side of the rotation shaft coupling part 153 between the rotation shaft 135 and the rotation shaft 135 .

Meanwhile, referring to FIG. 2 , a plurality of anti-rotation grooves 154 and discharge guide grooves 155 are formed on the rear surface of the turning head plate part 151 .

The plurality of anti-rotation grooves (precisely anti-rotation ring) 154 is to form an anti-rotation mechanism 160 for preventing the rotation of the orbiting scroll 150 together with the anti-rotation pin 161, and a plurality of anti-rotation grooves 154 is formed at a predetermined interval along the circumferential direction.

In addition, the plurality of anti-rotation grooves 154 are formed to correspond one-to-one with the plurality of anti-rotation pins 161 . Anti-rotation ring 162 is inserted into each of the plurality of anti-rotation grooves 154 and coupled thereto. Accordingly, each anti-rotation pin 161 is rotatably inserted and coupled to each anti-rotation ring 162 .

The discharge guide groove 155 is formed to be engraved by a predetermined depth at the center of the orbiting head plate part 151 , and inside the discharge guide groove 155 is a discharge space S3 for the refrigerant compressed in the compression chamber V to be described later. ), a discharge port 156 for discharging to is formed. The discharge port 156 is formed eccentrically from the center of the turning head plate 151 so as not to interfere with the rotation shaft coupling part 153 . Accordingly, the discharge guide groove 155 may also be formed eccentrically from the center of the turning head plate part 151 . A check valve 156a is installed at the discharge side end of the discharge port 156 to open and close the discharge port 156 to serve as a discharge valve.

A first sealing part 191 for blocking between the space forming the discharge chamber and the space forming the back pressure chamber may be formed around the discharge guide groove 155 .

Meanwhile, a support plate 180 is provided between the rear surface of the orbiting scroll 150 and the front surface of the rear housing 120 . A first sealing part 191 is provided on both sides of the support plate 180 in the axial direction, so that the space between the rear side of the orbiting scroll 150 and the front side of the rear housing 120 is divided into a plurality of spaces, that is, the discharge chamber. (S3) and the back pressure chamber (S2) are separated.

Since the support plate 180 is installed to reduce friction loss and abrasion with the rear housing 120 during the orbiting motion of the orbiting scroll 150, a material with greater wear resistance than the orbiting scroll 150 or the rear housing 120 can be formed with

In addition, the support plate 180 may be mounted on a plate support part 121 of the rear housing 120 to be described later and fixed between the coupling surface of the rear housing 120 and the main housing 110 . In this case, gaskets (not shown) may be provided on both sides or one side of the support plate 180 in the axial direction. Alternatively, the gasket may be positioned radially outward than the support plate 180 .

In addition, a plurality of pin holes (unsigned) through which the anti-rotation pins 161 are coupled are formed in the support plate 180 at predetermined intervals along the circumferential direction. A pin hole (unsigned) is formed at a position corresponding to the anti-rotation ring 162 provided in the orbiting scroll. The pin hole (unsigned) is approximately equal to or slightly larger than the anti-rotation pin 161 .

In addition, an oil communication hole 182 is formed in the support plate 180 . The oil communication hole 182 may be formed around the pin hole 181 . For example, the oil communication hole 182 may be formed inside the pin hole 181 .

However, the oil communication hole 182 may be formed outside the pin hole 181 or may be formed on the same circumference as the pin hole 180b. In some cases, the oil communication hole 182 overlaps the pin hole (unsigned) or one pin hole (unsigned) is formed larger than the other pin hole (unsigned) to form the oil communication hole 182. may be substituted.

The electric compressor according to the present embodiment as described above is operated as follows.

When power is applied to the electric part 130, the rotating shaft 135 rotates together with the rotor 132 and transmits a rotational force to the orbiting scroll 150, and the orbiting scroll 150 is an anti-rotation ring 162. The rotational movement is performed with respect to the fixed scroll 140 by the anti-rotation pin 161 . Then, the volume of the compression chamber V is reduced while continuously moving toward the center side.

Then, the refrigerant flows into the motor room S1 as a suction space through the intake port 111 , and the refrigerant flowing into the motor room S1 is a flow path formed on the outer circumferential surface of the stator 131 and the inner circumferential surface of the main housing 110 . Alternatively, it is sucked into the compression chamber V through the gap between the stator 131 and the rotor 132 .

Then, the refrigerant is compressed by the orbiting scroll 150 and the fixed scroll 140 and discharged to the rear housing 120 through the discharge port 156 . The refrigerant discharged to the rear housing 120 is separated from oil.

The separated oil is circulated as follows.

The rear housing 120 forms the orbiting scroll 150 and the discharge chamber S3 and the back pressure chamber S2. After the oil is separated from the refrigerant discharged to the discharge chamber S3, it is supplied to the back pressure chamber S2 through a decompression process. The oil supplied to the back pressure chamber S2 is moved to each bearing surface and the compression chamber V through the oil recovery passage 157 .

Specifically, a discharge pressure space 123 in which the discharged refrigerant is accommodated is formed in the center of the rear housing 120 . The discharge pressure space part 123 is formed in a cylindrical shape that is opened toward the turning head plate part 151 . The discharge pressure space 123 is covered by one side of the orbiting head plate 151 in which the discharge port 156 is formed, thereby forming the discharge chamber S3.

The refrigerant discharged through the discharge port 156 is accommodated in the discharge chamber S3 .

An oil separation space 124 into which the refrigerant of the discharge chamber S3 flows is formed on the rear side of the discharge chamber S3.

An exhaust port 125 through which the refrigerant flowing into the oil separation space 124 is discharged is formed at one side of the oil separation space 124 .

However, an oil separator 124a is installed in the exhaust port 125 , and the refrigerant flowing into the oil separation space 124 passes through the oil separator 124a and is separated from oil and then discharged to the exhaust port 125 .

The separated oil is stored in the oil separation chamber S4 formed in the oil separation space 124 .

In addition, the rear housing 120 forms a back pressure chamber S2 to which the oil of the oil separation chamber S4 is supplied and to support the orbiting scroll 150 . The back pressure chamber S2 is formed between the front side surface of the rear housing formed around the discharge pressure space 12 and the turning head plate 151 . The back pressure chamber S2 and the discharge chamber S3 are separated by a first sealing part 191 .

The rear housing 120 has an intermediate pressure space 122 that communicates with the back pressure chamber S2 and is positioned around the discharge pressure space 123 . The intermediate pressure space portion 122 is formed in a cylindrical shape that is opened toward the turning head plate portion 151 . The intermediate pressure space 122 may be formed in plurality along the circumference of the discharge pressure space 123 . However, the present invention is not limited thereto, and may be changed according to the shape of the rear housing. For example, the intermediate pressure space 122 may be formed in an annular shape along the circumference of the discharge pressure space 123 .

A communication passage 126 is formed between the intermediate pressure space 122 and the oil separation chamber S4 . The oil stored in the oil separation chamber S4 is supplied to the intermediate pressure space 122 through the communication passage 126 , and then is supplied to the back pressure chamber S2 through the oil communication hole 182 . The oil supplied to the back pressure chamber S2 is supplied to the compression chamber V or the bearing surface through the oil recovery passage 157 .

The oil supplied to the bearing surface flows into the motor chamber (S1) and then re-introduced into the compression chamber (V) together with the refrigerant to repeat the process of circulation.

When the oil in the oil separation chamber (S4) is supplied to the back pressure chamber (S2) without a decompression process, the orbiting scroll 150 is excessively floated and wear due to compression between the orbiting scroll 150 and the fixed scroll 140 may occur. can

Accordingly, the communication passage 126 is provided with a pressure reducing unit 200 for depressurizing the oil in the oil separation chamber S4 to an intermediate pressure.

Specifically, the decompression flow path Df having a relatively small cross-sectional area is formed in the decompression unit 200 , and the oil is decompressed while passing through the decompression flow path Df. Since the process of decompression of oil passing through the decompression passage is a well-known technique in the prior art, a detailed description thereof will be omitted.

The length of the decompression flow path Df provided in the decompression unit 200 according to an embodiment of the present invention may be changed.

In the pressure reduction passage Df provided in the pressure reducing unit 200 according to the present embodiment, the length of the pressure reduction passage Df may be changed according to a pressure difference between the oil separation chamber S4 and the back pressure chamber S2.

A pressure difference is generated between the oil separation chamber S4 and the back pressure chamber S2 by the pressure reducing unit 200 . The pressure difference may increase as the electric compressor is operated.

Specifically, when the pressure difference increases, the length of the reduced pressure passage Df increases, and when the pressure difference decreases, the length of the reduced pressure passage Df decreases.

When the length of the pressure reduction flow path Df is fixed without being changed, the amount of oil passing through the pressure reduction unit 200 may be changed due to a pressure difference between the oil separation chamber S4 and the back pressure chamber S2 .

When the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 increases, the amount of oil passing through the pressure reducing unit 200 increases, and when the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 decreases, the pressure reduction unit 200 ), the amount of oil passing through is reduced.

However, in the present embodiment, when the pressure difference increases, the length of the reduced pressure passage Df is increased, so that the resistance of the oil passing through the reduced pressure passage Df is increased. Thereby, an increase in the oil supply amount due to an increase in the pressure difference can be suppressed.

In addition, in the present embodiment, when the pressure difference is reduced, the length of the reduced pressure passage Df is reduced, so that the resistance of the oil passing through the reduced pressure passage Df is reduced. Thereby, it can be suppressed that the oil supply amount is reduced due to a decrease in the pressure difference. The length at which the oil passing through the reduced pressure flow path Df receives resistance may be defined as a "resistance length".

That is, the decompression unit 200 according to the present embodiment may reduce the difference in the oil supply amount according to the pressure difference.

In other words, the pressure reducing unit 200 according to the present embodiment can supply oil almost uniformly even when a pressure difference occurs.

Hereinafter, the decompression unit 200 according to an embodiment and a modified example of the present invention will be described in detail with reference to FIGS. 4 to 16 .

4 is a partial perspective view illustrating the decompression unit 200 of FIG. 1 . FIG. 5 is a cross-sectional view showing the pressure reducing unit of FIG. 1 . FIG. 6 is a cross-sectional view showing the pressure reducing unit of FIG. 1 .

Referring to FIG. 4 , a communication passage 126 for communicating the oil separation chamber S4 and the back pressure chamber S2 is formed through the rear housing 120 provided in the electric compressor of the present invention. The communication passage 126 is formed with a predetermined length from the oil separation chamber S4 toward the back pressure chamber S2.

The communication passage 126 includes an inlet 126a opened toward the oil separation chamber S4 and an outlet 126b opened toward the back pressure chamber S2. In addition, the communication passage 126 has a communication hole 126c that passes between the inlet 126a and the outlet 126b.

In the illustrated embodiment, the inlet 126a and the outlet 126b are formed to have the same diameter as the communication hole 126c. However, this may be changed according to the shape of the communication passage 126 . For example, the inlet 126a and the outlet 126b may have a larger diameter than the communication hole 126c.

The communication passage 126 is provided with a decompression unit 200 for decompressing the oil passing through the communication passage 126 .

The decompression unit 200 includes a decompression pin 210 inserted into the communication hole 126c and an elastic member 220 for pressing the decompression pin 210 .

The pressure reducing pin 210 may be formed in a cylindrical shape having a circular cross-section. However, the present invention is not limited thereto, and the decompression pin 210 may be formed in a D-cut columnar and polygonal columnar shape along the longitudinal direction.

The pressure reducing pin 210 is formed to extend a predetermined length along the longitudinal direction of the communication hole 126c and is inserted into the communication hole 126c.

The pressure reducing pin 210 is formed to have a cross-sectional area of a size smaller than the cross-sectional area of the communication hole 126c, whereby there is a flow path through which oil can pass between the outer peripheral surface of the pressure reducing pin 210 and the inner peripheral surface of the communication hole 126c. is formed The oil is decompressed to an intermediate pressure while passing through the flow path formed between the pressure reducing pin 210 and the communication hole 126a.

That is, the pressure reduction flow path Df is formed between the outer peripheral surface of the pressure reducing pin 210 and the inner peripheral surface of the communication hole 126c.

The pressure reducing pin 210 may be partially inserted into the communication hole 126c. A portion of the pressure reducing pin 210 protrudes toward the inlet 126a and is positioned to be exposed to the oil separation chamber S4 , and the remainder of the pressure reduction pin 210 may be inserted into the communication hole 126c. The length of the portion inserted into the communication hole 126c of the decompression pin 210 may be defined as an “insertion length”.

In one embodiment, the length of the pressure reducing pin 210 may be formed to be greater than the height of the oil separation chamber (S4). Through this, a portion of the pressure reducing pin 210 may be inserted into the communication hole 126c even in a state in which the pressure reducing pin 210 protrudes and comes into contact with one side of the oil separation chamber S4. As a result, the decompression pin 210 can be prevented from falling out from the communication hole 126c. The height of the oil separation chamber S4 means a distance between two surfaces of the oil separation chamber S4 facing each other in the longitudinal direction of the pressure reducing pin 210 .

An elastic member 220 is positioned at one end of the pressure reducing pin 210 facing the outlet 126b. The elastic member 220 is supported by the support end 126d protruding inward from the inner circumferential surface of the outlet 126b.

When the other side of the pressure reducing pin 210 facing the oil separation chamber S4 is pressurized by the pressure difference, the insertion length of the pressure reducing pin 210 is increased. When the insertion length of the pressure reducing pin 210 is increased, the elastic member 220 is compressed to press the pressure reducing pin 210 toward the oil separation chamber S4.

When the pressure difference is reduced, the pressure reducing pin 210 is moved to the oil separation chamber S4 by the elastic member 220 , and through this, the insertion length of the pressure reducing pin 210 may be reduced.

That is, the insertion length of the pressure reducing pin 210 may be changed by a pressure difference between the oil separation chamber S4 and the back pressure chamber S2 .

In one embodiment, the insertion length of the pressure reducing pin 210 may be formed to be greater than or equal to the first length (L1) and less than or equal to the second length (L2). The first length L1 means a length at which the pressure reducing pin 210 is inserted into the communication hole 126c at a minimum, and the second length L2 is the maximum length at which the pressure reduction pin 210 is inserted into the communication hole 126c. means the length inserted into

Since the communication passage Df is formed between the outer peripheral surface of the inserted portion of the pressure reducing pin 210 and the inner peripheral surface of the communication hole 126c, the length of the communication passage Df is equal to or greater than the first length L1 and the second length L2. ) can be formed below.

That is, when the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is increased, the length of the communication passage Df is increased, so that the resistance length of the communication passage Df can be increased. When the pressure difference is increased, the oil supply per unit time is increased, and when the resistance length is increased, the oil supply per unit time is decreased. Therefore, if the resistance length of the communication passage Df is increased when the pressure difference is increased, it is possible to suppress the increase in the oil supply amount per unit time due to the increase in the pressure difference.

In addition, when the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is reduced, the length of the communication passage Df may be reduced, so that the resistance length of the communication passage Df may be reduced. When the pressure difference is reduced, the oil supply per unit time is reduced, and when the resistance length is reduced, the oil supply per unit time is increased. Therefore, if the resistance length of the communication passage Df is reduced when the pressure difference is reduced, it is possible to suppress the decrease in the oil supply amount per unit time due to the decrease in the pressure difference.

As a result, it is possible to suppress the fluctuation of the oil supply amount per unit time due to the increase or decrease of the pressure difference between the oil separation chamber S4 and the back pressure chamber S2.

That is, the difference in the oil supply amount generated by the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 may be reduced.

That is, even when the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 varies, the oil supply amount per unit time can be maintained substantially constant.

That is, since the supply amount of oil per unit time can be designed as the minimum supply amount to ensure the reliability of the electric compressor, when the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 increases, the oil in the back pressure chamber S2 is excessive. supply can be suppressed.

Since oil does not escape from the oil separation chamber S4 to the back pressure chamber S2 at an excessive speed, the design capacities of the oil separator 124a and the oil separation chamber S4 may be reduced. As a result, the electric compressor can be miniaturized, and the cost required for manufacturing the electric compressor can be reduced.

In the illustrated embodiment, the elastic member 220 may be composed of a spring (spring). However, the present invention is not limited thereto, and the elastic member 220 may be formed of various members having elastic force.

Referring to FIG. 5 , the pressure reducing pin 210 is inserted into the communication hole 126c with a first length L1. The insertion length of the pressure reducing pin 210 is designed to be included within a predetermined length range, and the first length L1 is the length at which the pressure reduction pin 210 is minimally inserted into the communication hole 126c in the predetermined length range. .

The predetermined length range may be set in consideration of the degree of occurrence of the pressure difference of the electric compressor.

Specifically, when the maximum value of the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is relatively large, the predetermined length range may be designed to be relatively wide.

Also, when the maximum value of the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is relatively small, the predetermined length range may be designed to be relatively narrow.

A pressure reduction passage Df is formed between an outer peripheral surface of a portion of the pressure reducing pin 210 inserted into the communication hole 126c and an inner peripheral surface of the communication hole 126c. The reduced pressure flow path Df is formed with a first length L1.

In a state in which the reduced pressure flow path Df is formed with the first length L1 , the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is relatively small.

When the pressure reduction flow path Df is formed with the first length L1 , the pressure applied to one end surface of the pressure reduction pin 210 toward the oil separation chamber S4 may be offset by the elastic force of the elastic member 220 .

When the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is relatively small, the amount of oil supplied to the back pressure chamber S2 per unit time is relatively reduced.

However, since the pressure reduction passage Df is formed to have the shortest length L1 in the design range, the resistance length of the pressure reduction passage Df is formed to be the shortest in the design range. Accordingly, the amount of oil supplied per unit time moved to the back pressure chamber S2 is increased.

That is, since the resistance length is formed to be short when the pressure difference is formed to be relatively small, the decrease in the oil supply amount per unit time due to the decrease in the pressure difference is compensated by the increase in the oil supply amount per unit time due to the decrease in the resistance length. can

That is, when the pressure difference is formed to be relatively small and the oil supply amount per unit time is reduced, the length of the reduced pressure flow path Df is reduced, so that the oil supply amount per unit time can be increased.

Referring to FIG. 6 , the pressure reducing pin 210 is inserted into the communication hole 126c with a second length L2. The insertion length of the pressure reducing pin 210 is designed to be included within a predetermined length range, and the second length L2 is the length at which the pressure reduction pin 210 is maximally inserted into the communication hole 126c in the predetermined length range. .

The description of the design of the predetermined length range is replaced with the above-mentioned bar.

As the pressure reducing pin 210 is inserted into the second length L2 , the pressure reduction passage Df is formed with the second length L2 .

The process of increasing the insertion length of the pressure reducing pin 210 is as follows.

First, as the electric compressor is driven, the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is increased. When the pressure difference is increased, the pressure applied to one side of the pressure reducing pin 210 toward the oil separation chamber S4 is increased.

When the pressure applied to the pressure reducing pin 210 is increased, the pressure reducing pin 210 is moved toward the outlet 126b while compressing the elastic member 220 . That is, when the pressure applied to the pressure reducing pin 210 is increased, the insertion length of the pressure reducing pin 210 is increased.

When the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is gradually increased and the pressure applied to the pressure reducing pin 210 is greater than a predetermined pressure value, the pressure reducing pin 210 extends to the second length L2 through the communication hole 126c. is inserted into In an embodiment, the predetermined pressure value may be a value designed to allow the elastic member 220 to be maximally compressed.

In a state in which the pressure reduction flow path Df is formed with the second length L2 , a pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is relatively large.

When the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is relatively large, the amount of oil supplied to the back pressure chamber S2 per unit time is relatively increased.

However, since the pressure reduction passage Df is formed to have the longest length L2 in the design range, the resistance length of the pressure reduction passage Df is formed to be the longest in the design range. Accordingly, the amount of oil supplied per unit time moved to the back pressure chamber S2 may be reduced.

That is, since the resistance length is formed to be long when the pressure difference is relatively large, the increase in the oil supply amount per unit time due to the decrease in the pressure difference is attenuated by the decrease in the oil supply amount per unit time due to the increase in the resistance length. can

That is, when the pressure difference is formed to be relatively large, it can be suppressed from excessively increasing the oil supply amount per unit time.

5 and 6 , the insertion length of the pressure reducing pin 210 may be varied by the elastic force of the elastic member 220 and the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 .

When the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is gradually increased, the pressure reducing pin 210 gradually compresses the elastic member 220 toward the back pressure chamber S2, and thereby the insertion length of the pressure reducing pin 210 is increased. can be increased.

In addition, when the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is gradually reduced, the pressure reducing pin 210 is moved toward the oil separation chamber S4 by the elastic member 220 , whereby the pressure reduction pin 210 is The insertion length may be increased.

That is, as the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 increases, the length of the pressure reduction passage Df increases, and as the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 decreases, the pressure reduction passage ( The length of Df) is reduced.

The increase in the oil supply amount per unit time due to the increase in the pressure difference is attenuated by the decrease in the oil supply amount per unit time due to the increase in the length of the reduced pressure passage Df.

In addition, the decrease in the oil supply amount per unit time due to the decrease in the pressure difference is compensated by the increase in the oil supply amount per unit time due to the decrease in the length of the reduced pressure passage Df.

As a result, the difference in the oil supply amount per unit time supplied to the back pressure chamber S2 can be reduced. Thereby, oil can be supplied approximately evenly within a small error range without being excessively supplied.

As a result, it can be suppressed that oil is supplied in excess of an amount necessary for maintaining the reliability of the electric compressor.

Due to this, it is suppressed that an excessive amount of oil is supplied to the compression chamber, which may increase the volume of the refrigerant supplied into the compression chamber. As a result, compression efficiency can be improved.

In addition, supply of excessive oil to the oil separator 127a can be suppressed, so that oil is not separated from the oil separator 127a and discharged together with the refrigerant can be suppressed.

In addition, the use of the oil separator 124a having an excessively larger capacity than the amount required to maintain the reliability of the electric compressor is excluded, whereby the oil separation chamber S4 can be downsized. As a result, the electric compressor can be downsized.

In addition, since the oil separator 124a having a smaller capacity is used compared to the prior art, the price of the oil separator 124a is reduced. As a result, the manufacturing cost of the electric compressor can be reduced.

7 is a partial perspective view illustrating another embodiment of the decompression unit 200 of FIG. 1 . 8 is a cross-sectional view illustrating the decompression unit 200 of FIG. 7 . 9 is a cross-sectional view illustrating the decompression unit 200 of FIG. 7 .

Referring to FIG. 7 , a communication space 127 opened toward the oil separation chamber S4 may be recessed in one side 124b of the oil separation chamber S4 in which the communication passage 126 is formed.

The inlet 126a of the communication passage 126 is formed on the bottom surface of the communication space 127 . The inlet 126a of the communication passage 126 and the communication space 127 communicate with each other.

The communication space 127 is recessed by a predetermined height in the longitudinal direction of the pressure reducing pin 210 . Also, the communication space 127 may have a larger diameter than the communication hole 126c.

A stop member 230 for limiting the longitudinal movement of the pressure reducing pin 210 may be provided on one side 124b of the oil separation chamber S4.

The stop member 230 is formed in a substantially rectangular plate shape, and extends radially inward with respect to the central axis of the communication space 127 at a portion adjacent to the open portion of the communication space 127 .

On one side adjacent to the periphery of the open portion of the communication space 127 of the stop member 230 , a fixing hole 231 penetrated by the fastening member 234 is formed therethrough.

The fastening member 234 is inserted into and coupled to the one side surface 124b after passing through the fixing hole 231 , whereby the stopping member 230 may be fixed to the one side surface 124b. In one embodiment, the fastening member 234 may be a screw threaded coupling member. The fastening member 234 may be screwed with the coupling groove 124c recessed in the one side 124b.

The other side opposite to the one side on which the fixing hole 231 of the stop member 230 is formed is spaced apart from the communication space 127 by a predetermined distance and partially overlaps in the longitudinal direction of the pressure reducing pin 210 and the pressure reducing pin 210 . .

Among the portions of the stop member 230 , the contact surface 233 partially overlapping with the pressure reducing pin 210 is in contact with one end surface of the pressure reducing pin 210 moving toward the oil separation chamber S4 . Through this, the maximum length that can protrude from the inlet 126a of the pressure reducing pin 210 may be limited.

Accordingly, the pressure reducing pin 210 is moved to the oil separation chamber (S4) and can be prevented from being separated from the communication passage (126).

In addition, the pressure reducing pin 210 and the through hole 232 may be formed on the other side of the stop member 230 having a smaller diameter than the pressure reducing pin 210 . The space in which the through hole 232 is formed may overlap the pressure reduction pin 210 and the pressure reduction pin 210 in the longitudinal direction.

In a state in which the pressure reducing pin 210 is in contact with the stop member 230 , one end surface of the pressure reducing pin 210 facing the oil separation chamber S4 may be pressurized by the oil introduced into the through hole 232 .

In the illustrated embodiment, the stop member 230 includes a rounded portion surrounding an arc having a diameter equal to or greater than that of the pressure reducing pin 210 . In addition, the diameter of the through hole 232 formed in the stopping member 230 is formed smaller than the diameter of the pressure reducing pin (210). That is, a portion of the stopping member 230 positioned between the circumference of the through hole 232 and the circumference of the stopping member 230 partially overlaps the pressure reducing pin 210 .

However, the shape of the stopping member 230 is not limited to the above-described structure, and the stopping member 230 is formed in various shapes that can partially overlap the pressure reducing pin 210 and the pressure reducing pin 210 in the longitudinal direction. can be

8 and 9 , when the pressure reducing pin 210 is inserted into the communication hole 126c by the first length L1, one cross section of the pressure reducing pin 210 toward the oil separation chamber S4 is a stopping member. It is partially in contact with the contact surface 233 of 230 .

When the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is increased and one end face of the pressure reduction pin 210 toward the oil separation chamber S4 is pressurized, the length at which the pressure reduction pin 210 is inserted into the communication hole 126c. may be increased up to the second length L2.

The description of the structure and effect of changing the length in which the pressure-reducing pin 210 is inserted replaces the above-mentioned bar.

The decompression unit 200 according to the present embodiment is formed to be substantially the same in structure and function as the above-described embodiment. However, in this embodiment, there is a difference in that the communication space 127 is formed and the stopper 2301 is provided. Configurations other than those of which descriptions are omitted may be understood with reference to the above-described embodiments.

10 is a cross-sectional view illustrating a modified example of the decompression unit 200 of FIG. 7 . 11 is a cross-sectional view illustrating the decompression unit 200 of FIG. 10 .

10 and 11 , a buffer space 2321a in which one end of the pressure reduction pin 210 is accommodated is recessed by a predetermined depth on one side of the stop member 2301 facing the pressure reduction pin 210 .

The buffer space 2321a is formed with a larger diameter than the diameter of the pressure reducing pin 210 . A through hole 2321 is formed in one side of the buffer space 2321a facing the pressure reducing pin 210 . The through hole 2321 is formed to have a smaller diameter than the diameter of the pressure reducing pin 210 . A contact surface 2321b partially overlapping with the pressure reducing pin 210 is formed at a portion where the through hole 2321 and the buffer space 2321a are connected.

When the pressure reducing pin 210 is moved toward the oil separation chamber S4, one end of the pressure reducing pin 210 is guided in the buffer space 2321a, and then comes into contact with the contact surface 2321b. Through this, the maximum length that can protrude from the inlet 126a of the pressure reducing pin 210 may be limited.

In addition, in the illustrated embodiment, the buffer space 2321a may be provided with a buffer member 240 having an elastic force. One side of the buffer member 240 is fixed to the contact surface 2321b, and the other side of the buffer member 240 is fixed to the pressure reducing pin 210 .

The end of the pressure reducing pin 210 facing the oil separation chamber is pressed toward the intermediate pressure space 122 by the buffer member 240 , and the end of the pressure reducing pin 210 facing the intermediate pressure space is attached to the elastic member 220 . by the oil separation chamber (S4) side.

In one embodiment, the buffer member 240 may be formed to press the pressure reducing pin 210 into the intermediate pressure space 122 at all positions of the pressure reducing pin 210 .

Accordingly, when the pressure reducing pin 210 is moved toward the oil separation chamber S4 due to a decrease in the pressure difference, the pressure reducing pin 210 is pressed in the opposite direction to the movement direction by the buffer member 240 . As a result, it is possible to prevent the pressure-reducing pin 210 from moving rapidly toward the oil separation chamber S4 to collide with the contact surface 2321b.

However, when the pressure difference is abruptly changed to 0, such as when the power of the electric compressor 10 is turned off, the pressure reducing pin 210 may be moved relatively rapidly toward the contact surface 2321b.

In consideration of this, in a state where the pressure difference is 0, the end of the oil separation chamber side of the pressure reducing pin 210 may be spaced apart from the contact surface 2321b by a predetermined distance. The predetermined distance may be defined as a “buffer distance”.

That is, the pressure difference is 0 and the buffer member 240 and the elastic member 220 press the pressure reducing pin 210 at a position where the end of the oil separation chamber side of the pressure reducing pin 210 is spaced apart by the buffer distance from the contact surface 2321b, respectively. forces can be balanced.

That is, when the pressure difference is 0, the pressure reducing pin 210 is pressed toward the intermediate pressure space 122 when the contact surface 2321b is closer than the buffer distance, and when the contact surface 2321b is farther than the buffer distance, the contact surface 2321b ) is pressed toward

When the pressure difference abruptly changes to 0, the speed of the pressure reduction pin 210 is attenuated in the process where the pressure reduction pin 210 is closer to the contact surface 2321b than the buffer distance, and through this, the pressure reduction pin 210 is a stop member A collision with 2301 can be prevented.

As a result, it can be suppressed that the durability of the pressure reducing pin 210 is reduced due to the collision with the stop member 2301 .

As a result, the reliability of the pressure reducing pin 210 and the stopping member 2301 may be improved.

Furthermore, noise generation due to the collision of the decompression pin 210 may be suppressed.

In this embodiment, the buffer member 240 may be provided with a spring. However, the present invention is not limited thereto, and the buffer member 240 may be formed of various elastic materials capable of preventing the pressure reducing pin 210 from colliding with the stop member 2301 .

When the pressure reducing pin 210 is inserted into the communication hole 126c with a first length L1, one end face of the pressure reducing pin 210 toward the oil separation chamber S4 is a contact surface 2321b of the stop member 2301 and partially in contact.

When the pressure difference between the oil separation chamber S4 and the back pressure chamber S2 is increased and one end face of the pressure reduction pin 210 toward the oil separation chamber S4 is pressurized, the length at which the pressure reduction pin 210 is inserted into the communication hole 126c. may be increased up to the second length L2.

The description of the structure and effect of changing the length in which the pressure-reducing pin 210 is inserted replaces the above-mentioned bar.

The decompression unit 200 according to this modified example is formed to be substantially the same in structure and function as the embodiment described above with reference to FIG. 7 . However, in this embodiment, there is a difference in that the buffer space 2321a is formed in the stopping member 2301 and the buffer member 240 is provided in the buffer space 2321a. Configurations other than those of which descriptions are omitted may be understood with reference to the above-described embodiments.

12 is a cross-sectional view illustrating another modified example of the decompression unit 200 of FIG. 7 . FIG. 13 is a cross-sectional view illustrating the decompression unit of FIG. 12 .

12 and 13 , a buffer member 241 is attached to one end of the pressure reducing pin 210 facing the contact surface 2321b.

Through this, when the pressure reducing pin 210 collides with the contact surface 2321b, the amount of impact may be reduced by the buffer member 241 .

In the illustrated embodiment, the buffer member 241 may be formed of a material such as a sponge that can alleviate the impact. However, the present invention is not limited thereto, and the buffer member 241 has elastic force and may be formed in various shapes capable of reducing the amount of impact received by the pressure reducing pin 210 . The pressure reducing unit 200 according to this modified example is shown in FIG. 10 . and substantially identical in structure and function to the modified example described above in FIG. 11 . However, in this modified example, the cushioning member 241 relieves the impact force at the moment when the pressure reducing pin 210 collides with the stopping member 2301 , and in the above-described modified example, the cushioning member 240 is the pressure reducing pin 210 . There is a difference in preventing a collision by reducing the speed in the process of moving to the stop member 2301 .

The buffer member 241 according to the present modification does not prevent the collision of the pressure reducing pin 210, but can reduce the amount of impact applied to the pressure reducing pin 210 at a lower cost.

In addition, a configuration in which description is omitted may be understood with reference to the above-described modified example.

14 is a partial perspective view illustrating another modified example of the decompression unit 200 of FIG. 7 . FIG. 15 is a cross-sectional view showing the decompression unit of FIG. 14 . FIG. 16 is a cross-sectional view showing the decompression unit of FIG. 14 .

14 to 16 , a stop member 2303 covering the open portion of the communication space 127 is shown.

The stopping member 2303 includes a filter unit 2313 filtering foreign substances contained in oil and a filter housing 2323 surrounding the filter unit 2313 .

In an embodiment, the filter unit 2313 may be formed of a mesh material including pores. The pores may be formed with a diameter smaller than the diameter of the foreign material contained in the oil.

The filter housing 2323 is coupled to the circumference of the filter unit 2313 , and a plurality of fastening holes 2323a are formed through the filter housing 2323 along the circumference of the filter unit 2313 . A fastening member 2333 is inserted through the fastening hole 2323a, and the fastening member 2333 passing through the fastening hole 2323a is inserted into and coupled to one side 124b of the oil separation chamber S4. Through this, the stopping member 2303 may be coupled to one side 124b of the oil separation chamber S4.

The oil moving to the back pressure chamber S2 also flows into the compression chamber V or the bearing surface. At this time, the oil may be mixed with fine metal foreign substances and may be introduced into the compression chamber V or the bearing surface together with the oil. Foreign substances flowing into the compression chamber (V) can cause leakage between the compression chambers (V) by abrading the contact surface between the fixed scroll (140) and the orbiting scroll (150), and foreign substances entering the bearing surface are the bearings. Wearing the surface can shorten the life of the bearing or cause friction loss.

In this modified example, the stop member 2303 for limiting the insertion length of the pressure reducing pin 210 includes a filter unit 2313 for filtering foreign substances.

Therefore, the stop member 2303 can limit the insertion length of the pressure reducing pin 210 and prevent foreign substances from flowing into the compression chamber V or the bearing surface.

As a result, it is possible to prevent the pressure-reducing pin 210 from being separated, and at the same time, the occurrence of refrigerant leakage or friction loss between the compression chambers V due to foreign substances can be suppressed.

The decompression unit 200 according to this modified example is formed to be substantially the same in structure and function as the embodiment described above with reference to FIG. 7 . However, in this embodiment, there is a difference in that the stopping member 2303 is provided with a filter unit 2313 capable of filtering foreign substances contained in oil. Configurations other than those of which descriptions are omitted may be understood with reference to the above-described embodiments.

Although the above has been described with reference to the preferred embodiment of the present invention, those of ordinary skill in the art can variously modify and change the present invention within the scope without departing from the spirit and scope of the present invention described in the claims below. You will understand that you can.

100: electric compressor
101: compression module
102: inverter module
105: compression unit
111: intake port
112: scroll support surface
110: main housing
120: rear housing
120a: bulkhead
121: plate support
122: intermediate pressure space portion
123: discharge pressure space part:
124: oil separation space
124a: oil separator
125: exhaust port
126: flue euro
126a: inlet
126b: outlet
126c: communication hole
126d: support
127: communication space
130: electric part
131: stator
132: rotor
135: rotation shaft
135a: main bearing part
135b: sub bearing part
135c: eccentric
136: oil supply passage
140: fixed scroll
141: fixed head plate part
142: side wall portion
143: fixed wrap
145: intake
146: rotation shaft support protrusion
147: rotation shaft receiving part
150: orbiting scroll
151: turning head plate
152: swivel wrap
153: rotation shaft coupling part
154: anti-rotation groove
155: discharge guide home
156: outlet
156a: check valve
157: oil guide passage
160: anti-rotation mechanism
161: anti-rotation pin
162: anti-rotation ring
171: main bearing
172: sub bearing
180: support plate
182: oil through hole
191: first sealing part
192: second sealing part
193: third sealing part
200: decompression unit
Df: reduced pressure flow path
210: pressure reducing pin
220: elastic member
230: stopping member
231: fixing hole
232: through hole
233: contact surface
234: fastening member
2301: stopping member
2311: fixing hole
2321: through hole
2321a: buffer space
2321b: contact surface
2331: fastening member
240: buffer member
241: buffer member
2303: stop member
2313: filter unit
2323: filter housing
2323a: fastener
2333: fastening member
V: compression chamber
V1: Suction pressure chamber
S1: Motor room
S2: back pressure chamber
S3: discharge chamber
S4: Oil separation chamber
S5: storage space
L1: first length
L2: second length

Claims (15)

housing;
a driving motor provided in the housing;
a compression unit operated by the driving motor to compress the refrigerant;
an oil separation chamber provided at one side of the compression unit to separate oil from the refrigerant discharged from the compression unit;
a back pressure chamber provided on the one side or the other side opposite to the one side of the compression unit to support the compression unit;
a communication passage connecting the oil separation chamber and the back pressure chamber; and
and a decompression unit provided in the communication passage to reduce the pressure of the fluid moving from the oil separation chamber to the back pressure chamber,
The decompression unit,
a pressure reducing pin inserted into the communication passage by a predetermined length;
and an elastic member positioned on one side of the pressure reducing pin facing the back pressure chamber to press the pressure reducing pin,
The predetermined length is equal to or greater than a predetermined first length and less than or equal to a predetermined second length,
A pressure reduction passage through which the fluid moving from the oil separation chamber to the back pressure chamber is decompressed is formed between a portion of the pressure reducing pin inserted into the communication passage and the communication passage,
electric compressor. According to claim 1,
As the pressure difference between the oil separation chamber and the back pressure chamber increases, the predetermined length into which the pressure reducing pin is inserted increases,
electric compressor. According to claim 1,
As the pressure difference between the oil separation chamber and the back pressure chamber decreases, the predetermined length into which the pressure reducing pin is inserted is reduced,
electric compressor. According to claim 1,
At one side of the elastic member facing the back pressure chamber, a support end protruding from an inner circumferential surface of the communication passage to support the elastic member is formed,
electric compressor. According to claim 1,
The oil separation chamber is provided with a stopping member spaced by a predetermined distance from the inlet of the communication passage opened toward the oil separation chamber and partially overlapping the pressure reducing pin in the longitudinal direction of the pressure reducing pin,
electric compressor. 6. The method of claim 5,
A buffer member having an elastic force is provided on one side of the stopping member facing the pressure-reducing pin,
The buffer member partially overlaps in the longitudinal direction of the pressure reducing pin and the pressure reducing pin,
electric compressor. According to claim 1,
A communication space open toward the oil separation chamber is formed in the oil separation chamber,
The inlet of the communication passage opened toward the oil separation chamber is formed in the communication space,
The open portion of the communication space is covered by a filter member,
The filter member overlaps the pressure reduction pin in the longitudinal direction of the pressure reduction pin,
electric compressor. main housing;
an electric part provided in the inner space of the main housing;
a compression unit provided in the inner space of the main housing and driven by the electric unit to compress the refrigerant;
a rear housing provided on the other side opposite to one side of the compression part facing the electric part and coupled to the main housing;
an oil separation chamber formed in the rear housing and separating oil from the refrigerant discharged from the compression unit;
a back pressure chamber formed between the rear housing and the compression unit and supporting the compression unit;
a communication passage formed through the rear housing to communicate between the oil separation chamber and the back pressure chamber; and
and a decompression unit provided in the communication passage to reduce the pressure of the fluid moving from the oil separation chamber to the back pressure chamber,
The decompression unit,
a pressure reducing pin inserted into the communication passage by a predetermined length;
and an elastic member positioned on one side of the pressure reducing pin facing the back pressure chamber to press the pressure reducing pin,
The predetermined length is equal to or greater than a preset first value and less than or equal to a preset second value,
A pressure reduction passage through which the fluid moving from the oil separation chamber to the back pressure chamber is decompressed is formed between a portion of the pressure reducing pin inserted into the communication passage and the communication passage,
electric compressor. 9. The method of claim 8,
As the pressure difference between the oil separation chamber and the back pressure chamber increases, the predetermined length into which the pressure reducing pin is inserted increases,
electric compressor. 9. The method of claim 8,
As the pressure difference between the oil separation chamber and the back pressure chamber decreases, the predetermined length into which the pressure reducing pin is inserted is reduced,
electric compressor. 9. The method of claim 8,
At one side of the elastic member facing the back pressure chamber, a support end protruding from an inner circumferential surface of the communication passage to support the elastic member is formed,
electric compressor. According to claim 1,
A communication space having a larger diameter than that of the communication passage is recessed in the oil separation chamber,
The inlet toward the oil separation chamber of the communication passage communicates with the communication space,
electric compressor. 13. The method of claim 12,
A stopping member adjacent to the communication space is coupled to one side of the oil separation chamber on which the communication space is formed,
The stopping member is spaced apart from the inlet of the communication passage by a predetermined distance, and partially overlaps the pressure reducing pin in the longitudinal direction of the pressure reducing pin,
electric compressor. 14. The method of claim 13,
A buffer member having an elastic force is provided on one side of the stopping member facing the pressure-reducing pin,
The buffer member partially overlaps in the longitudinal direction of the pressure reducing pin and the pressure reducing pin,
electric compressor. 13. The method of claim 12,
A filter member covering the communication space is coupled to one side of the oil separation chamber on which the communication space is formed,
The filter member overlaps the pressure reducing pin and the pressure reducing pin in the longitudinal direction,
electric compressor.

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