KR102043157B1 - Motor operated compressor - Google Patents

Abstract

According to the present invention, an electric compressor can comprise: a first scroll; a second scroll configured to form a pair of compression chambers between the second scroll and the first scroll while the second scroll is engaged to the first scroll to rotate; a frame unit fixed radially at the opposite side of the first scroll, wherein the second scroll is interposed between the frame unit and the first scroll, to form a back pressure space to radially support the second scroll; a rotary shaft formed to pass through the second scroll and the frame unit, and including a thrust unit that protrudes toward a radial direction between the second scroll and the frame unit to come in contact with the frame unit; and an elastic member interposed between the first scroll and the rotary shaft to apply an elastic force to the rotary shaft in the direction of the frame unit.

Description

Electric Compressor {MOTOR OPERATED COMPRESSOR}

The present invention relates to an electric compressor.

In general, the compressor that serves to compress the refrigerant in the vehicle air conditioning system has been developed in various forms, and in recent years, the development of the electric compressor driven by the electric using the motor is actively made according to the trend of the lengthening of the automotive parts.

Among the various compression methods, the motor-driven compressor mainly adopts a scroll compression method suitable for high compression ratio operation. In the scroll-type electric compressor, a motor part made of a rotating motor is installed in the sealed casing, and a compression part made of a fixed scroll and a swing scroll is installed at one side of the motor part. In addition, the motor unit and the compression unit are connected to the rotating shaft so that the rotational force of the motor unit is transmitted to the compression unit. The rotational force transmitted to the compression unit pivots the swinging scroll with respect to the fixed scroll to form two pairs of compression chambers, a suction chamber, an intermediate pressure chamber, and a discharge chamber. do.

In the scorrol compression method, a compressor having a shaft through structure in which a rotating shaft passes through a compression part has been disclosed. Specifically, the rotating scroll is formed with a rotating shaft coupling portion penetrating the center, the end of the rotating shaft rotatably inserted into the rotating shaft coupling portion may be made to be supported by the fixed scroll. With such a shaft through structure, the refrigerant cancels each other while the repulsive force and the compressive force are applied to the same plane with respect to the hard plate portion of the revolving scroll, thereby preventing the inclination of the revolving scroll due to the action of the compressive and repulsive force. Done.

Here, a back pressure chamber is formed between the swing scroll and the frame to press the swing scroll in close contact with the fixed scroll to maintain the closed state of the compression chamber. Usually, the back pressure chamber is formed to communicate with the intermediate pressure chamber or the discharge pressure chamber. Accordingly, the medium and the discharge pressure of refrigerant and oil are accommodated in the back pressure chamber to press the swing scroll in the direction toward the fixed scroll.

However, in such a shaft-through scroll structure, since the rotating shaft is not supported in the axial direction, the axial vibration of the rotating shaft increases. As a result, the refrigerant and the oil forming the back pressure leak out of the back pressure space through the contact surface between the frame and the rotating shaft, thereby causing a problem of failing to form a stable back pressure in the back pressure chamber.

In particular, when a certain amount of back pressure is not formed at the initial stage of the driving of the compressor, the behavior of the rotating shaft becomes unstable, causing a problem of delayed pressure formation in the compression chamber.

An object of the present invention is to provide a structure for improving the back pressure sealing between the rotating shaft and the frame forming the back pressure space in order to solve the above problems.

Furthermore, an object of the present invention is to prevent leakage of refrigerant and oil through the bearing surface between the frame and the rotating shaft due to the axial vibration of the rotating shaft, thereby forming a stable back pressure in the back pressure chamber.

In addition, another object of the present invention is to provide a structure for maintaining a stable mounting state of the rotating shaft.

In order to achieve the above object, the motor-driven compressor according to the present invention is a first scroll, a second scroll to form a pair of compression chambers with the first scroll while pivoting in engagement with the first scroll, the first scroll A frame portion fixed radially from an opposite side of the first scroll with two scrolls therebetween to form a back pressure space to support the second scroll in an axial direction; And a thrust portion protruding in the radial direction between the second scroll and the frame portion, the thrust portion contacting the frame portion, and the first scroll and the rotation shaft. Is disposed between, and may include an elastic member for applying an elastic force in the direction of the frame portion to the rotating shaft.

Here, the first scroll forms a rotating shaft receiving portion for receiving at least a portion of the rotating shaft to support the rotating shaft in a radial direction, the rotating shaft receiving portion extends in the axial direction of the rotating shaft, the elastic member is the rotating shaft receiving portion It may be provided in.

According to the invention, the rotating shaft receiving portion includes a support surface formed to face the end of the rotating shaft, the elastic member is made of a coil spring, it may be in contact with the end of the rotating shaft and the support surface, respectively. In this case, the elastic member is supported by the support surface, it is possible to elastically support the rotating shaft.

In addition, the end of the rotating shaft is formed with a protrusion projecting in the axial direction from the center, the elastic member may be fitted to the protrusion. For this reason, the elastic member can rotate with the rotation of the rotating shaft.

In this case, the support surface is formed with a guide groove recessed to correspond to the coil spring to guide the rotation of the coil spring according to the rotation of the rotary shaft, one end of the elastic member is to be accommodated in the guide groove Can be.

In addition, it may further include a bearing member disposed between the support surface and the coil spring.

The apparatus may further include a sealing member disposed between the rotating shaft and the frame part and having an annular shape along an outer circumference of the rotating shaft.

The thrust portion may include a surface facing the axial direction of the frame portion in an axial direction, and the sealing member may be disposed between the surface facing the axial direction and the axial direction of the frame portion.

According to the present invention, the rotating shaft receiving portion includes an inner circumferential surface formed to correspond to the outer circumferential surface of the rotating shaft, and the inner circumferential surface is formed stepped along the axial direction of the rotating shaft to form a seating surface facing the end of the rotating shaft. The elastic member may be formed of a leaf spring to contact the end of the rotating shaft and the seating surface, respectively.

Here, the elastic member may include a first elastic member made of a coil spring and a second elastic member made of a leaf spring, and may include at least one of the first elastic member or the second elastic member.

According to the present invention, the thrust portion may include an inclined surface that is formed to be inclined along the axial direction of the rotation shaft, and the frame portion may include a sealing surface that is formed to correspond to the inclined surface.

Here, the sealing member is an electric compressor, characterized in that provided between the inclined surface and the sealing surface.

In contrast, according to the present invention, the frame portion is formed with a frame bearing portion extending in the axial direction to receive at least a portion of the rotating shaft, the first bearing and the inclined surface disposed between the bearing portion and the rotating shaft and the It may include a second bearing disposed between the sealing surface.

Here, the first bearing and the second bearing may be integrally formed.

According to the present invention, since the elastic member disposed between the rotating shaft and the fixed scroll applies an elastic force to the rotating shaft in the direction of the frame portion, the sealing force between the rotating shaft and the frame portion can be improved.

As a result, a stable back pressure can be formed in the back pressure chamber between the swing scroll and the frame portion.

In addition, since the rotating shaft is continuously subjected to an elastic force toward the frame portion, the axial vibration of the rotating shaft is reduced, and the behavior of the rotating shaft can be stabilized.

Further, according to the present invention, in the case of using the elastic member made of the leaf spring, the axial length of the rotating shaft accommodating portion can be reduced, which can contribute to the miniaturization of the compressor.

In addition, according to the present invention, the thrust surface is formed to be inclined so that the frame portion can be supported in the axial direction and the radial direction to the rotating shaft, the behavior of the rotating shaft can be more stable.

1 is a perspective view showing the compressor module and the inverter module separated from the electric compressor according to an embodiment of the present invention.
2 is a cross-sectional view showing the interior of the electric compressor according to FIG.
3 is a cross-sectional side view of the main housing in the motor-driven compressor according to FIG. 2;
4 is a front view of the main housing in FIG. 3 seen from the rear side;
5 is a cross-sectional view showing a rotating shaft and a bearing for supporting the rotating shaft according to the present invention.
FIG. 6 is a plan view illustrating a coupling relationship between a non-involute shaped swing wrap and a fixed wrap in an electric compressor according to an embodiment of the present invention; FIG.
Figure 7 is a front view of the second scroll in accordance with an embodiment of the present invention from the front side.
FIG. 8 is a sectional side view of the second scroll according to FIG. 7; FIG.
9 is a cross-sectional side view showing a coupling relationship between a rotating shaft, first and second scrolls according to an embodiment of the present invention;
10 is a cross-sectional side view showing a coupling relationship between a rotating shaft, first and second scrolls according to another embodiment of the present invention;
11 is a sectional view showing the inside of the electric compressor according to another embodiment of the present invention.
12 is a sectional side view of the main housing of the motor-driven compressor according to FIG. 11;
13 is a sectional side view showing the main housing in the motor-driven compressor according to a modification of another embodiment of the present invention.

Hereinafter, the electric compressor according to the present invention will be described in detail based on the embodiment shown in the accompanying drawings.

1 is a perspective view of a compressor module and an inverter module separated from the electric compressor according to an embodiment of the present invention, Figure 2 is a cross-sectional view showing the interior of the electric compressor according to FIG.

As shown therein, the scroll-type electric compressor according to the present invention (hereinafter, abbreviated as an electric compressor) is combined with a compressor module 101 for compressing refrigerant and a front side of the compressor module 101 and a compressor module. Inverter module 201 for controlling the driving of the 101 may be made. The compressor module 101 and the inverter module 201 may be assembled in succession or may be assembled after being fabricated independently of each other. Although the present embodiment will be described using the latter as a representative example, the compressor module and the inverter module may be independently manufactured in the form of a mixture of the former and the latter, but may be continuously assembled.

The compressor module 101 is a main housing 110 in which the inlet port 111 is formed so that the inner space forms the motor chamber S1 and communicates with the motor chamber, and the transmission unit fixed to the motor chamber S1 of the main housing 110. Compression unit 105 and compression unit 105 provided on one side of the drive motor 120 outside the main motor 110 and the main housing 110 to compress the refrigerant using the rotational force of the drive motor 120. It is coupled to the other side of the includes a rear housing 160 to form an oil separation chamber (S2).

As the main housing 110 is disposed in the transverse direction with respect to the ground, the drive motor 120 and the compression unit 105 are arranged along the transverse direction, and for convenience, designate the left side of FIG. 2 as the front side and the right side as the rear side. Will be explained.

The main housing 110 is formed in a cup cross-sectional shape in which the front end is opened and the rear end is partially blocked. Inverted front end of the main housing 110, the inverter housing 210 to be described later is coupled and sealed, the closed rear end of the main housing 110 frame 112 for supporting the compression section 105 integrally Is formed extending. In the frame portion 112 of the main housing 110, a frame bearing portion 113 through which the main bearing portion 132 of the rotating shaft 130 to be described later is rotatably supported is formed in a cylindrical shape.

A frame bearing 171 made of a bush bearing is inserted into and coupled to the frame bearing portion 113, and an inner circumferential surface of the frame bearing portion 113 is spaced apart from the main bearing portion 132 of the rotation shaft 130 to be described later. S3) may be in communication with the motor chamber S1. As the intake port 111 to which the suction pipe (not shown) is connected near the front end of the main housing 110 is formed, the motor chamber S1 of the present embodiment forms a kind of suction space. Therefore, the electric compressor according to the present embodiment forms a low pressure compressor as the refrigerant is sucked into the compression unit through the inner space of the main housing forming the motor compartment.

The main housing according to the present embodiment integrally forms the frame portion as described above. Accordingly, by eliminating the process of assembling the frame to the main housing separately, the assembly maneuverability can be reduced and assembly of the drive motor can be improved.

3 is a cross-sectional view of the main housing in a side view of the electric compressor according to FIG. 2, and FIG. 4 is a front view of the main housing in FIG. 3.

As shown therein, the axis center Ob1 of the frame bearing part 113 is formed to coincide with the axis center Om of the drive motor 120. To this end, the center of the outer diameter of the frame portion 112 and the center of the inner diameter (that is, the center of the first bearing portion) may be formed to coincide.

However, while the shaft center Ob1 of the frame bearing part 113 coincides with the shaft center Om of the driving motor 120, the outer diameter center Oo and the inner diameter center Oi of the frame part 112 do not coincide with each other. Can be formed. For example, as shown in FIGS. 3 and 4, the first protrusion 114 is formed at one radial side of the frame portion 112, and the first protrusion 114 is configured to communicate with the inside of the motor chamber S1. One flow passage 114a may be formed through. The first flow passage 114a may form a suction flow passage Fg for communicating the compression chamber V and the motor chamber S1 together with the second flow passage 154a of the second scroll 150, which will be described later.

On the other hand, the frame portion 112 is formed in such a way that the front side protrudes toward the center, that is, the frame bearing portion 113 toward the drive motor 120, the rear side of the frame portion 112 is the drive motor 120 It is formed to be recessed to be stepped at least two times in the direction toward the. Accordingly, the rear wall of the frame portion 112 is inserted into the pivoting plate portion of the first scroll to be described later, the scroll seating groove (112a) which is supported in the axial direction, the olddaming seating groove (180) that the anti-rotation mechanism is seated ( 112b) and the balance weight receiving groove 112c in which the balance weight 138 is rotatably received are formed, respectively. The scroll seating groove 112a, the old damling seating groove 112b, and the balance weight receiving groove 112c are continuously formed to form a kind of back pressure chamber S3.

In addition, the rear end of the frame bearing portion 113 protrudes in a direction toward the first scroll 140 to have a cylindrical shape, and a frame bearing 171 made of a bush bearing is inserted into the frame bearing portion 113. Are combined. Accordingly, the rear end of the frame bearing portion 113 forms the back pressure chamber S3 by forming the balance weight receiving groove 112c whose outer circumferential surface is described above.

Further, at the rear end of the frame bearing portion 113, an axial bearing surface 113a forming a thrust surface together with the thrust portion 135 of the rotating shaft 130 to be described later is formed. here,

Here, the axial bearing surface 113a of the frame bearing portion 113 and the axial bearing surface 135a of the thrust portion 135 provided on the rotating shaft 130 closely contact with the frame bearing 171 therebetween. The back pressure chamber S3 can be sealed. This prevents leakage through the thrust surface of the refrigerant and the oil forming the back pressure of the back pressure chamber S3, thereby making it possible to form a stable back pressure in the back pressure chamber S3. However, in this case, the refrigerant and the oil accumulated in the back pressure chamber S3 may again flow into the compression chamber through the back pressure hole (not shown) formed in the first scroll 150.

On the other hand, the drive motor 120, the stator 121 is inserted into the inner circumferential surface of the main housing 110, and the rotor is located inside the stator 121 and rotated by the interaction with the stator 121 ( 122). Rotor 122 is coupled to the rotating shaft 130 for transmitting the rotational force of the drive motor 120 to the compression unit 105 while rotating together with the rotor 122.

The stator 121 is fixed to the main housing 110 by shrinking (or hot pressing). Therefore, the stator 121 may be advantageous in reducing the insertion depth of the main housing 110 to facilitate the assembling work, and maintain the concentricity of the stator 121 in the process of shrinking the stator 121. have.

To this end, as shown in FIG. 3, the main housing 110 has a shaft of the stator 121 when the open end is referred to as the first end 110a and the end where the frame portion 112 is formed as the second end 110b. The length L1 from the center CL in the direction to the first end 110a may be shorter than the length L2 from the center CL in the axial direction of the stator 121 to the second end 110b. have. Accordingly, as described above, the insertion depth L3 for inserting the stator 121 into the motor chamber S1 of the main housing 110 may be shortened.

On the other hand, the rotating shaft 130 is coupled to the center of the rotor 122 by shrinkage (or hot pressing). The rotating shaft 130 may support both ends in the radial direction with the driving motor 120 interposed therebetween. However, as shown in this embodiment, one end of the rotation shaft 130 is a fixed end that is supported at one side of the driving motor 120, that is, two points in the radial direction from the frame part 112 and the second scroll 150, and the driving motor. The other end of the rotation shaft 130 coupled to the rotor 122 of 120 may be a free end in the radial direction.

5 is a cross-sectional view showing a rotating shaft and a bearing for supporting the rotating shaft according to the present invention.

As shown, the rotating shaft 130 is the shaft portion 131 coupled to the rotor 122, the main bearing portion 132 rotatably supported in the radial direction to the frame bearing portion 113, the second scroll 140 ) Is formed in the eccentric portion 133 coupled to the eccentric portion, the sub bearing portion 134 rotatably radially supported in the scroll bearing portion 156 of the first scroll 150. As described above, the main bearing part 132 and the sub bearing part 134 respectively support the rotation shaft 130 in the radial direction, and the eccentric part 133 may rotate the rotational force of the driving motor 120 in the second scroll 140. The second scroll 140 is swiveled by the Oldham ring 180 by transmitting the same.

In addition, an oil supply passage 136 is formed inside the rotary shaft 130 by a predetermined depth in a direction from the rear end to the front end, and the main bearing part 132 and the eccentric part in the middle of the oil supply passage 136. 133, the respective oil supply holes 137a, 137b, 137c are formed toward the outer circumferential surface of the sub bearing portion 134. This will be described later along with the oil supply structure.

Meanwhile, referring again to FIG. 2, the compression unit 105 is a pivoting scroll (hereinafter referred to as a second scroll) that is pivotally supported by the frame portion 112 of the main housing 110 in the axial direction as described above. A fixed scroll (or non-orbiting scroll) (hereinafter referred to as a first scroll) that is engaged with the second scroll 140 and fixedly coupled to the second end 110b that is engaged with the second scroll 140 and forms a closed end of the main housing 110. And 150. Two pairs of compression chambers V are formed between the second scroll 140 and the first scroll 150 during the pivoting movement of the second scroll 140. The compression chamber will be described later with the turning wrap and the fixing wrap.

The second scroll 140 is supported in the axial direction by the frame portion 112, and the anti-rotation mechanism for preventing the rotation of the second scroll 140 between the frame portion 112 and the second scroll 140. As the Oldham ring 180 is provided. The anti-rotation mechanism may be applied to pins and rings as well as olddam rings.

In addition, the second scroll 140 has a rotating scroll plate (hereinafter referred to as a rotating plate) 141 is formed in a substantially disk shape, and is engaged with the fixed wrap 153 to be described later on the rear surface of the rotating plate (141). Swivel wraps 142 forming compression chambers are formed on the inner and outer surfaces of the fixing wrap 153. The turning lap will be described later with the fixed lap.

The pivoting plate portion 141 is formed with a back pressure hole 141a for communicating the back pressure chamber S3 and the intermediate compression chamber V to each other. Accordingly, the oil or the refrigerant moves between the back pressure chamber S3 and the intermediate compression chamber V according to the difference between the pressure in the back pressure chamber S3 and the pressure in the intermediate compression chamber V.

In addition, a rotation shaft coupling portion 143 through which the eccentric portion 133 of the rotation shaft 130 is rotatably coupled is formed at the center of the pivot plate 141. The rotating shaft coupling portion 143 is formed in a cylindrical shape, and the third bearing 173 forming a bearing surface is inserted into and coupled to the eccentric portion 133 of the rotating shaft coupling portion 143. Accordingly, the rotating shaft coupling portion (or the third bearing) 143 is formed to overlap the turning wrap 142 in the radial direction, and the rotating shaft coupling portion 143 is a part of the turning wrap 142 formed at the innermost portion. do.

Meanwhile, as described above, the first scroll 150 may be coupled to the second end of the main housing 110 from the outside of the main housing 110. In this case, a sealing member such as a gasket may be provided between the main housing 110 and the first scroll 150.

Referring again to FIG. 5, one oil supply passage 136 and a plurality of oil supply holes 137a, 137b, and 137c may be formed in the rotation shaft 130. As described above, the oil supply passage 136 is formed in the axial direction by a predetermined depth in the front end direction at the end of the rotary shaft 130, that is, the rear end of the rotary shaft 130 accommodated in the oil guide space, a plurality of oil supply The holes 137a, 137b, and 137c may be formed at regular intervals along the axial direction in the middle of the oil supply passage 136.

The plurality of oil supply holes 137a, 137b, and 137c pass through the second oil supply hole 137b penetrating the outer circumferential surface of the sub bearing part 134 and the third oil supply hole 137c penetrating the outer circumferential surface of the eccentric portion 133. The first oil supply hole 137a may pass through the outer circumferential surface of the main bearing part 132.

Accordingly, the oil flowing into the oil supply passage 136 from the oil guide space passes through the second oil supply hole 137b, the third oil supply hole 137c, and the first oil supply hole 137a in turn, and thus each bearing surface. To be supplied.

Meanwhile, the turning wrap and the fixed wrap may each be formed in an involute shape. However, when the rotary shaft is coupled through the center of the second scroll, which is the orbiting scroll, as in this embodiment, the final compression chamber may be formed at an eccentric position, and a large pressure difference between the compression chambers may be generated. This is because, in the case of the axial through scroll compressor, the final compression chamber is eccentrically formed from the center of the scroll, so that the pressure in one compression chamber is significantly lower than the pressure in the other compression chamber. Therefore, in the axial through scroll compressor, it is advantageous to form the turning wrap and the fixed wrap in a non-involute shape as in the present embodiment.

6 is a plan view illustrating a coupling relationship between a non-involute shape swing wrap and a fixed wrap in an electric compressor according to an embodiment of the present invention.

As shown therein, the turning wrap 142 according to the present embodiment has a form in which a plurality of circular arcs having different diameters and origins are connected to each other, and the outermost curve may be formed in an approximately elliptical shape having a long axis and a short axis. have. The fixed wrap 153 may likewise be formed.

A central portion of the pivot plate 141 forms an inner end of the pivot wrap 142, and a rotation shaft coupling portion 143 through which the eccentric portion 133 of the rotation shaft 130 is rotatably inserted and coupled is formed in the axial direction. Can be. A third bearing 173 made of a bush bearing may be inserted into and fixed to an inner circumferential surface of the rotation shaft coupling part 143. The outer circumferential portion of the rotating shaft coupling portion 143 is connected to the turning wrap 142 to form a compression chamber V together with the fixed wrap 153 in the compression process.

In addition, the rotation shaft coupling portion 143 is formed at a height overlapping the pivot wrap 142 on the same plane, and the eccentric portion 133 of the rotation shaft 130 is disposed at the height overlapping the pivot wrap 142 on the same plane. Can be. As a result, the repulsive force and the compressive force of the refrigerant are offset to each other while being applied to the same plane based on the pivot plate, so that the inclination of the first scroll 140 due to the action of the compressive force and the repulsive force may be prevented.

In addition, the rotating shaft coupling portion 143 is formed with a recess 143a which engages with the protrusion 153a of the fixed wrap 153, which will be described later, on an outer circumferential portion facing the inner end of the fixed wrap 153. One side of the 143a is formed with an increasing portion 143b that increases in thickness from the inner circumference portion to the outer circumference portion of the rotary shaft coupling portion 143 along an upstream side of the compression chamber V in the forming direction. This makes the compression path of the first compression chamber V1 immediately before the discharge longer, so that the compression ratio of the first compression chamber V1 can be increased closer to the compression ratio of the second compression chamber V2.

The other side of the recess 143a is formed with an arc compression surface 143c having an arc shape. The diameter of the circular arc compression surface 143c is determined by the inner end thickness of the fixed wrap 153 (ie, the thickness of the discharge end) and the turning radius of the turning wrap 142. Increasing increases the diameter of the arc compression surface 143c. As a result, the thickness of the turning wrap around the circular arc compression surface 143c may be increased to ensure durability, and the compression path may be longer to increase the compression ratio of the second compression chamber V2.

In addition, a protruding portion 153a protruding toward the outer circumferential portion of the rotating shaft coupling portion 143 is formed near the inner end (suction end or starting end) of the fixed wrap 153 corresponding to the rotating shaft coupling portion 143. The contact portion 153b protruding from the protrusion portion and engaged with the recess portion 143a may be formed in the 153a. That is, the inner end of the fixed wrap 153 may be formed to have a larger thickness than other portions. As a result, the wrap strength of the inner end portion that receives the greatest compressive force among the fixed wraps 153 may be improved, thereby improving durability.

On the other hand, the compression chamber (V) is formed between the fixed hard plate portion 151 and the fixed wrap 153, and the turning wrap 142 and the rotating hard plate portion 141, the suction chamber, the intermediate pressure chamber along the direction of the wrap The oil separation chamber may be formed continuously.

The compression chamber V includes a first compression chamber V1 formed between the outer surface of the turning wrap 142 and the inner surface of the fixed wrap 153, and the inner surface and the fixed wrap 153 of the turning wrap 142. The second compression chamber (V2) is formed between the outer surface of the. That is, the first compression chamber V1 includes a compression chamber formed between two contact points P11 and P12 generated by contact between the inner surface of the fixed wrap 153 and the outer surface of the turning wrap 142. 2 The compression chamber V2 includes a compression chamber formed between two contact points P21 and P22 generated by contact between the outer surface of the fixed wrap 153 and the inner surface of the turning wrap 142.

Here, the first compression chamber V1 immediately before the discharge has an angle having a larger value among the angles formed by the center of the eccentric portion, that is, the center O of the rotary shaft coupling portion and the two lines connecting the two contact points P11 and P12, respectively. When? Is?, At least immediately before the discharge start,? <360 ° and the distance l between the normal vectors at the two contact points P11 and P12 also has a value greater than zero.

Since the fixed wrap and the swing wrap according to the present embodiment have a smaller volume than the case where the first compression chamber immediately before the discharge has the fixed wrap and the swing wrap formed of the involute curve, the swing wrap 142 And the compression ratio of the first compression chamber V1 and the compression ratio of the second compression chamber V2 may be improved without increasing the size of the fixing wrap 153.

Meanwhile, the rear housing 160 is coupled to the second surface 150b of the second scroll 150, and the compression chamber together with the second surface 150b of the second scroll 150 inside the rear housing 160. Oil separation chamber (S2) may be formed to accommodate the refrigerant discharged from (V).

Here, separate protrusions (not shown), such as a main side fastening protrusion 115 and an inverter side fastening protrusion 211, which will be described later, are formed on the outer circumferential surfaces of the rear housing 160 and the second scroll 150, respectively, to be bolted together. Alternatively, the fastening bolt passing through the edge of the rear housing 160 may be coupled to the edge of the second scroll 150. A sealing member such as a gasket may be provided between the rear housing 160 and the second scroll 150.

On the other hand, the inverter housing 210 may be coupled to the opposite end of the rear housing 160, that is, the open end of the main housing 110, from both ends of the main housing 110.

7 is a front view showing a second scroll according to an embodiment of the present invention from the front side, and FIG. 8 is a cross-sectional view showing the second scroll according to FIG.

As shown in the drawing, the first scroll 150 has a fixed scroll hard plate portion (hereinafter, fixed hard plate portion) 151 having a substantially disc shape, and the edge of the fixed hard plate portion 151 of the main housing 110. A side wall portion 152 is formed that is coupled to the frame side end. The front surface of the fixed plate portion 151 is formed with a fixed wrap 153 is engaged with the turning wrap 142 to form a compression chamber (V). As described above, the fixing wrap 153 may be formed in an involute shape together with the turning wrap 142, but may be formed in various other shapes.

In addition, the outer circumferential surface of the side wall portion 152 is formed to protrude in the radial direction so as to correspond to the first protrusion 114 described above, and the first flow passage 114a described above in the second protrusion 154. In addition, a second flow path 154a constituting the suction flow path Fg may be formed. Accordingly, the outer diameter center Oso of the second scroll 150 may be formed to have a center different from the center Ob2 of the second bearing portion 113.

The second flow path 154a constituting the suction flow path Fg may be formed in the axial direction, or may be inclined as shown in FIG. 6. When the second flow path 154a is formed in the axial direction, the outer diameter of the fixed hard plate part 151 may be enlarged to increase the wound length of the fixed wrap 153 relative to the same outer diameter of the main housing 110. When the 154a is formed to be inclined, the compressor may be miniaturized by reducing the wound length of the fixed wrap 153 to the same capacity of the compression chamber.

In addition, as the first flow passage 114a and the second flow passage 154a constituting the suction flow path Fg are formed in the first protrusion 114 and the second protrusion 154, respectively, the suction flow path Fg is formed in the compressor. It may be formed close to the outer peripheral surface. Accordingly, the refrigerant sucked into the compression chamber (V) through the suction flow path (Fg) in the motor chamber (S1) can be quickly heat exchanged with the outside of the compressor, through which the body of the refrigerant sucked into the compression chamber (V) Lowering the enemy can reduce suction loss. In particular, in the case of the second flow path 154a, since the second scroll 150 is provided outside the main housing 110, the second scroll 154a is located closer to the outside than that inserted into the main housing 110. The heat dissipation effect of the somewhat heated refrigerant can be further increased while passing through the seal.

In addition, the outer circumferential surface of the side wall portion 152 may be provided with a weight loss groove 152a for preventing deformation while reducing the weight of the second scroll 150. The weight gain groove 152a may be formed at a plurality of intervals along the circumferential direction, or one may be formed long in the circumferential direction.

Furthermore, since the outer circumferential surface of the side wall portion 152 of the second scroll 150 is located outside the main housing 110, the outer diameter of the second scroll 150 is greater than or equal to the inner diameter of the main housing 110. Can be formed. Thus, the outer diameter of the second scroll 150 can be increased based on the outer diameter of the same compressor, and through this, the length of the fixed wrap 153 and the turning wrap 142 is increased to increase the wound diameter of the compression chamber V. Inhalation volume can be increased.

In addition, a discharge port 155 is formed at the central portion of the fixed plate portion 151 to communicate the final compression chamber V with the oil separation chamber S2 to be described later to guide the discharge of the refrigerant. The discharge port 155 may be formed to penetrate through the compression chamber V in the axial direction or the inclined direction of the fixed plate portion 151 toward the oil separation chamber S2. Only one discharge port 155 may be formed so as to communicate with both of the first compression chamber V1 and the second compression chamber V2, and may communicate with the first compression chamber V1 and the second compression chamber V2 independently. The first discharge hole 155a and the second discharge hole 155b may be formed to be formed.

9 is a cross-sectional view illustrating a coupling relationship between a rotating shaft, a first scroll, and a second scroll according to an embodiment of the present invention.

Referring to FIG. 9 together with FIG. 8, the rotation shaft 130 is formed to penetrate the second scroll 150 and the frame portion 112 of the main housing 110, and in this case, one end of the rotation shaft 130. Is disposed facing the first scroll 150. As described above, a scroll shaft bearing portion 156 is formed at the center of the fixed hard plate portion 151 of the first scroll 150 to radially support the rotation shaft 130. The scroll bearing portion 156 forms a rotation shaft accommodating portion 156c therein to accommodate one end of the rotation shaft 130.

The scroll bearing portion 156 may be formed by enlarging the thickness of the fixed hard plate portion 151 thickly. However, in the latter case, not only the weight of the second scroll 150 is increased, but also the unnecessary portion is formed to be thick, the length of the discharge port 155 may be increased, thereby increasing the dead volume. Therefore, as shown, it can be formed to protrude a part of the fixed plate portion 151. That is, it may be formed to extend in the axial direction toward the rear housing 160 from the fixed plate portion 151.

The second bearing 172 may be inserted into the scroll bearing portion 156 to support the rotation shaft 130 in the radial direction. The scroll bearing portion 156 is formed in a cylindrical shape in which the rear surface is blocked, and the second bearing 172 constituting the bearing surface with the sub bearing portion 134 of the rotation shaft 130 is inserted into and coupled to the inner circumferential surface 156b. The second bearing 172 may be made of a bush bearing or may be made of a needle bearing.

Here, the scroll bearing portion 156 may be formed longer in the axial direction than the accommodated length of the rotation shaft 130. That is, the rotation shaft accommodating part 156c may be formed to extend toward the rear housing. In this case, as shown in the rotation shaft accommodating part 156c, an extra space that is not occupied by the rotation shaft 130 remains. The extra space of the rotary shaft accommodating portion 156c may be utilized as an oil guide space communicating with the oil guide passage 157.

The rotary shaft accommodating part 156c is positioned between the oil guide passage 157 and the oil supply passage 136 which will be described later. Oil guide flow passage 157 is in the oil separation chamber (S2), the oil supply passage 136 is each bearing surface provided in the outer peripheral surfaces of the main bearing portion 132, the sub bearing portion 134 and the eccentric portion 133 Can be communicated with.

The oil guiding flow path 157 may be formed in the first scroll 150 or may be formed in the rear housing 160 when the oil guide flow path 157 is formed by enlarging the thickness of the fixed hard disk part 151 thickly.

For example, when the oil guide passage 157 is formed of the first scroll 150, the oil guide passage 157 may be formed to penetrate through the scroll bearing portion 156 extending to protrude toward the rear housing 160.

One end of the oil guide passage 157 passes through the side surface of the scroll bearing portion 156 to communicate with the scroll receiving portion 156c, and the other end communicates with the oil storage tank. The oil storage tank is formed on the opposite side outside the oil separation chamber S2. Referring back to Figure 2, the oil storage tank is provided below the oil separation chamber (S2), the high-pressure oil separated from the refrigerant in the oil separation chamber (S2) of the rear housing 160 is the oil guide flow path (157) It can be quickly moved to the rotating shaft receiving portion (156c) along. The oil moved to the rotation shaft accommodating part 156c may be rapidly supplied to each bearing surface through the oil supply passage 136 and the respective oil supply holes 137a to 137c by the pressure difference.

Meanwhile, according to the present invention, an elastic member 159 is disposed between the first scroll 150 and the rotation shaft 130 to apply an elastic force to the rotation shaft 130 in the frame portion 112 direction. More specifically, the elastic member 159 is provided in the rotation shaft receiving portion 156c.

The rotation shaft receiving portion 156c may include a support surface 156a formed to face the end of the rotation shaft 130 and an inner circumferential surface 156b formed to correspond to the outer circumferential surface of the rotation shaft 130. Here, the outer circumferential surface of the rotating shaft 130 may correspond to the sub bearing part 134 of the rotating shaft 130. In other words, the inner circumferential surface 156b of the rotation shaft receiving portion 156c may be formed to surround the sub bearing portion 134.

The elastic member 159 provided in the rotation shaft accommodating part 156c is disposed to contact the end of the rotation shaft 130 and the support surface 156b, respectively. The elastic member 159 continuously applies an elastic force to the rotation shaft 130. In this case, the sealing force between the thrust portion 135 and the frame portion 112 of the rotation shaft 130 may be improved, so that the gap between the frame portion 112 and the rotation shaft 130, that is, the thrust portion 135. ) Through the bearing surface between the frame portion 112 and the refrigerant and oil can be prevented from leaking to the motor chamber (S1). Thus, a stable back pressure can be formed in the back pressure chamber S3. In particular, since the back pressure is not formed during the initial driving, the driving failure can be effectively prevented.

The elastic member 159 may be made of a coil spring. On the other hand, the end of the rotating shaft 130 may be provided with a protrusion protruding from the central portion toward the support surface. The outer diameter of the protrusion may be smaller than the outer diameter of the sub bearing portion 134 accommodated in the scroll bearing portion 156. In addition, the outer diameter of the protrusion may be formed to be substantially the same as the inner diameter of the elastic member 159 made of a coil spring. Here, one end of the elastic member 159 made of a coil spring may be fitted to the protrusion. As a result, the phenomenon in which the elastic member 159 made of the coil spring deviates from the correct position according to the rotation of the rotation shaft 130 can be prevented.

On the other hand, the other end of the elastic member 159 that is supported in contact with the support surface 156a may also be displaced or twisted as it rotates. Although not shown, according to the present invention, a guide groove (not shown) recessed in the axial direction may be formed in the support surface 156a to guide the rotation of the elastic member 159 made of the coil spring. The guide groove may have a diameter in a size corresponding to the outer diameter of the elastic member 159 made of a coil spring. The guide groove may be formed in a circular shape corresponding to a circular or coil spring. The elastic member 159 is inserted into the guide groove, and may guide the rotation of the elastic member 159 according to the rotation of the rotation shaft 130.

On the other hand, as the other end of the elastic member 159 made of a coil spring rotates, friction with the support surface 156b of the rotary shaft receiving portion 156c is continuously generated. At this time, heat is generated due to friction between the other end of the elastic member 159 and the support surface 156b, so that the overall efficiency of the compressor may be reduced, and durability of the elastic member 159 may be reduced. In addition, the chips that are separated from the elastic member 159 or the support surface 156b flow into the compression chamber, causing a problem that the compression chamber is damaged.

Accordingly, a coating layer capable of reducing friction may be formed on the surface of the support surface 156c in contact with the elastic member 159. Alternatively, the first scroll 150 may be formed of a cast iron material having excellent wear resistance.

Although not shown, according to the present invention, a bearing member (not shown) may be disposed between the other end of the elastic member 159 made of the coil spring and the support surface 156b to prevent mutual friction. The bearing member (not shown) may be a rolling bearing such as a ball bearing or a rolling bearing such as a bush bearing. In addition, since the oil is continuously supplied by the oil guide passage 157, friction may be minimized.

10 is a cross-sectional view illustrating a coupling relationship between a rotating shaft, a first scroll, and a second scroll according to another embodiment of the present invention.

Referring to the drawings, unlike the above-described embodiment, in the present embodiment, the elastic member 159 'may be formed of a leaf spring.

More specifically, as described above, since the second bearing 172 is fitted to the portion surrounding the sub bearing portion 134 of the inner circumferential surface 156b ', the sub bearing portion 134 of the inner circumferential surface 156b' is disposed. The inner diameter of the enclosing portion may be larger than the inner diameter of the extended portion of the inner circumferential surface 156b '. The inner diameter of the extended portion of the inner circumferential surface 156b 'may be formed to be substantially the same as or larger than the outer diameter of the second bearing portion 134 of the rotation shaft 130.

That is, the inner circumferential surface 156b ′ of the rotation shaft accommodating part 156c may be formed stepwise along the axial direction, and a seating surface 156b ″ facing the end of the rotation shaft 130 is formed in the stepped region. In this case, the elastic member 159 'made of a leaf spring is disposed between the seating surface 156b "and the end of the rotating shaft 130, and the elastic member 159' is a seating surface 156b" and the rotating shaft 130. The elastic member 159 'is supported by the seating surface 156b ", and is able to elastically support the rotation shaft 130, respectively.

In addition, as described above, the end of the rotation shaft 130 is formed with a protrusion protruding in the axial direction. The center of the elastic member 159 'made of a leaf spring is formed so as to penetrate through the protrusion. That is, a through hole may be formed at the center of the elastic member 159 ′ formed of a leaf spring. The diameter of the through hole is formed to correspond to the size of the protrusion protruding from the end of the rotation shaft 130. That is, the diameter of the through hole may be formed equal to or larger than the outer diameter of the protrusion.

Meanwhile, referring back to FIGS. 2 and 3, the rotation shaft 130 includes a thrust portion 135 protruding in the radial direction between the second scroll 140 and the frame portion 112. That is, the thrust part 135 may extend in a radial direction between the main bearing part 132 and the eccentric part 133. The axial bearing surface 135a of the thrust portion 135 forms a thrust surface together with the axial bearing surface 113a of the first bearing portion 113. Since the rotating shaft 130 receives elastic force in the direction of the frame portion 112 by the elastic members 159 and 159 ', the sealing force of the thrust surface may be improved.

Meanwhile, a sealing member 116 made of a polymer compound such as Teflon may be disposed on the thrust surface. The sealing member 116 is formed in an annular annular shape, and may be provided with at least a part inserted into a groove formed by being recessed in the axial bearing surface 113a. Due to this. The refrigerant and oil in the back pressure chamber S3 can be effectively prevented from leaking into the motor chamber S1.

11 is a cross-sectional view illustrating an interior of a motor-driven compressor according to still another embodiment of the present invention, FIG. 12 is a cross-sectional view of a main housing in the motor-driven compressor according to FIG. 11, and FIG. 13 is a view of another embodiment of the present invention. Side view of the main housing in the motor-driven compressor according to the modification.

In the above description, the description of the same / similar parts as the present embodiment will be omitted.

As described above, the rotation shaft 130 is formed with a thrust portion 135 'protruding in the radial direction. Here, the thrust part 135 ′ may include an inclined surface that is formed to be inclined along the axial direction of the rotation shaft 130. In other words, the thrust part 135 ′ may be formed to continuously reduce the inner diameter toward the frame part 112.

In addition, the frame part 112 may be formed with a sealing surface 113a ′ formed to be inclined to correspond to the inclined surface formed to be inclined. In other words, the frame portion 112 may be formed to correspond to the inclined thrust portion 135 ′. Because of this, the contact area, that is, the area of the thrust surface is increased, the sealing force between the rotating shaft 130 and the frame portion 112 may be increased. As the rotation shaft 130 can be supported in the axial direction and the radial direction, the behavior of the rotation shaft 130 can be more stable.

In addition, according to the present embodiment, a thrust bearing 174 may be disposed between the thrust surface and the sealing surface. Thrust bearing 174 may be made of a bush bearing. In this case, the thrust bearing 174 is formed corresponding to the thrust surface. When looking at thrust bearing 174 from the side, it may look trapezoidal in shape. That is, the fourth bearing may be formed to reduce the inner diameter and the outer diameter in the direction of the frame portion 112.

In FIGS. 11 and 12, the frame bearing 171 and the thrust bearing 174 are formed of separate members. However, unlike the illustrated example, the fourth bearing 174 may be integrally formed with the first bearing. That is, the frame bearing 171 is formed so that the inner diameter and the outer diameter are constantly extended along the axial direction in the region facing the main bearing portion 132, and the inner diameter and the outer diameter of the frame bearing 171 may be extended. Can be. In this case, the sealing area of the back pressure chamber may increase because the adhesion area between the bearings therebetween increases.

FIG. 13 is a cross-sectional view of a main housing in a side view of a motor-driven compressor according to another embodiment of the present invention. FIG.

Unlike the above-described embodiment, in the present embodiment, the sealing member 175 may be disposed on the inclined thrust surface. A groove is formed in any one surface of the inclined surface of the thrust part 135 and the sealing surface 113a 'of the frame part 112, and the sealing member 175 may be disposed with at least a part inserted into the groove. .

What has been described above is only embodiments for implementing the electric compressor according to the present invention, the present invention is not limited to the above embodiments, and within the scope not departing from the gist of the present invention as claimed in the following claims. Anyone with ordinary knowledge in the field of the present invention will have the technical idea of the present invention to the extent that various modifications can be made.

Claims (12)

First scroll;
A second scroll which engages with the first scroll and forms a pair of compression chambers with the first scroll while pivoting;
A frame part fixed radially from an opposite side of the first scroll with the second scroll therebetween to form a back pressure space to support the second scroll in an axial direction; And
A rotating shaft formed to penetrate the second scroll and the frame part, the thrust part protruding in a radial direction between the second scroll and the frame part and contacting the frame part; And
And an elastic member disposed between the first scroll and the rotating shaft to apply an elastic force to the rotating shaft in the direction of the frame portion. The method of claim 1,
The first scroll forms a rotation shaft receiving portion for receiving at least a portion of the rotation shaft to support the rotation axis in the radial direction,
The rotating shaft receiving portion extends in the axial direction of the rotating shaft,
The elastic member is an electric compressor, characterized in that provided in the rotating shaft receiving portion. The method of claim 2,
The rotating shaft receiving portion,
A support surface formed to face an end of the rotation shaft,
The elastic member is made of a coil spring, the electric compressor, characterized in that in contact with the end of the rotary shaft and the support surface, respectively. The method of claim 3,
At the end of the rotating shaft is formed a protrusion projecting in the axial direction from the center,
And the elastic member is fitted to the protrusion. The method of claim 4, wherein
The support surface is formed with a guide groove recessed to correspond to the coil spring to guide the rotation of the coil spring according to the rotation of the rotary shaft,
One end of the elastic member is an electric compressor, characterized in that accommodated in the guide groove. The method of claim 4, wherein
And a bearing member disposed between the support surface and the coil spring. The method of claim 2,
The rotating shaft receiving portion includes an inner circumferential surface formed to correspond to the outer circumferential surface of the rotating shaft,
The inner circumferential surface is formed stepped along the axial direction of the rotary shaft, to form a seating surface facing the end of the rotary shaft,
The elastic member is composed of a leaf spring, the electric compressor, characterized in that in contact with the end of the rotary shaft and the seating surface, respectively The method of claim 1,
And a sealing member disposed between the rotating shaft and the frame portion and formed in an annular shape along an outer circumference of the rotating shaft. The method of claim 8,
The thrust portion includes an inclined surface inclined along the axial direction of the rotation axis,
The frame unit comprises a sealing surface formed to correspond to the inclined surface. The method of claim 9,
The sealing member is an electric compressor, characterized in that provided between the inclined surface and the sealing surface. The method of claim 9,
The frame portion is formed with a frame bearing portion extending in the axial direction to receive at least a portion of the rotation axis,
A first bearing disposed between the bearing portion and the rotation shaft; And
And a second bearing disposed between the inclined surface and the sealing surface. The method of claim 11,
And the first bearing and the second bearing are integrally formed.

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