Liquid receiver and refrigeration cycle device provided with liquid receiver

Abstract

Provided are a liquid receiver and a refrigeration cycle device provided with a liquid receiver, the liquid receiver comprising a horizontally placed container which includes a cylindrical container central portion, and a first container end portion and a second container end portion that are provided on both sides in the axial direction of the container central portion and that have an outwardly convex curved surface shape, the container storing a refrigerant, and an outlet pipe and an inlet pipe which are installed in the container and which each have one end that is formed to be open and is positioned within the container, wherein: a space inside the container includes a central region surrounded by a central cylindrical portion obtained by dividing the container central portion into three equal parts in the axial direction, a first region that is closer to the first container end portion side than the central region, and a second region that is closer to the second container end portion side than the central region; the other end of the outlet pipe is provided so as to be positioned in an upper part of the second region; the inlet pipe is provided such that the one end of the inlet pipe is positioned in the first region and an extension line of the one end to the outside of the pipe on a central axis of the opening portion intersects a part of an inner wall surface of the container that faces the first region, and the inlet pipe has a bent portion that is formed so as to be bent from a connecting portion with the container to said one end side within the container; and the angle formed by the pipe axis on the one end side of the bent portion and the pipe axis on the other end side thereof is greater than 90°.

Description

Receiver and refrigeration cycle device equipped with receiver

[0001] The present disclosure relates to a receiver that stores a refrigerant and a refrigeration cycle device that includes the receiver.

[0002] Generally, refrigeration cycle devices such as air conditioners are equipped with a receiver that temporarily stores excess refrigerant to prevent refrigerant shortages in the refrigerant circuit due to changes in operating conditions. Examples of receivers include an accumulator that is located on the suction side of the compressor and stores refrigerant flowing out of the evaporator, and a receiver that is located in a position in the refrigerant circuit where medium-pressure refrigerant flows and stores refrigerant flowing out of the condenser or evaporator.

[0003] In addition to storing excess refrigerant during operation, such a receiver is required to reliably return refrigeration oil discharged from the compressor along with the refrigerant to the compressor while limiting the amount of liquid refrigerant flowing into the compressor within the compressor's liquid backflow resistance. Here, the flow of liquid refrigerant into the compressor is called liquid backflow, and the liquid backflow resistance is the resistance to liquid backflow. The compressor's reliability can be maintained if the liquid backflow ratio (liquid refrigerant inflow rate / refrigerant circulation flow rate) is below a limit value. The amount of excess refrigerant varies depending on factors such as the compressor's operating frequency, but when the refrigeration cycle system is operating under conditions with a lower evaporation temperature, the refrigerant circulation flow rate tends to decrease and the amount of excess refrigerant tends to increase.

[0004] Typically, such a receiver includes a container and an inlet pipe and an outlet pipe that penetrate the container. Some such receivers have improved liquid backflow resistance (see, for example, Patent Document 1). In Patent Document 1, a partition plate with a communication hole is provided inside the container of the receiver to divide the container into a first chamber and a second chamber, with a refrigerant inlet pipe provided in the first chamber and a refrigerant outlet pipe provided in the second chamber. The liquid backflow resistance is improved by configuring the receiver so that a small amount of liquid refrigerant from the first chamber flows into the second chamber through the communication hole in the partition plate.

[0005] Japanese Patent Application Publication No. 8-110127

[0006] However, in Patent Document 1, the pressure loss of the refrigerant passing through the receiver increases by the amount that the refrigerant passes through the communication holes in the partition plate inside the receiver container. Therefore, in order to reduce the pressure loss of the refrigerant, it is considered to remove the partition plate inside the receiver container. However, in Patent Document 1, because the bend in the inlet pipe is a right angle (90°), centrifugal force is easily applied to the liquid refrigerant passing through the inlet pipe. The liquid refrigerant with high kinetic energy concentrates and collides with the liquid refrigerant stored at the bottom of the receiver, causing the liquid surface to become disturbed and wavy, resulting in a problem of liquid backflow.

[0007] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a receiver and a refrigeration cycle device equipped with a receiver that have improved liquid backflow resistance without installing a partition plate inside the container.

[0008] The receiver according to the present disclosure comprises a horizontally placed container having a cylindrical container center portion, and first and second container ends provided on both axial sides of the container center portion and having curved surfaces that convex outward, the container having a refrigerant stored therein, and an outlet pipe and an inlet pipe disposed on the container, each having an open end and positioned within the container, the space within the container being divided into three equal parts in the axial direction, the space within the container being divided into three equal parts in the axial direction, a central region surrounded by a central cylindrical portion, a first region closer to the first container end than the central region, and a second region closer to the first container end than the central region. a second region on a second end side of the container, the other end of the outlet piping being located above the second region, the inlet piping having one end located in the first region and an extension line of the central axis of an opening of the one end to the outside of the pipe intersecting with a portion of the inner wall surface of the container facing the first region, the inlet piping having a bent portion bent from a connection portion with the container to one end side of the container, the angle formed by the pipe axis on one end side of the bent portion and the pipe axis on the other end side is greater than 90°.

[0009] According to the present disclosure, the inlet pipe has one end located in the first region, an extension of the central axis of the opening at the one end intersects with a portion of the inner wall surface of the container facing the first region, and has a bent portion bent from the connection portion with the container to one end inside the container, and the angle between the pipe axis at one end of the bent portion and the pipe axis at the other end is greater than 90°. This reduces the application of centrifugal force to the liquid refrigerant passing through the inlet pipe, thereby preventing liquid refrigerant with high kinetic energy from being concentrated toward the lower part of the inlet pipe. As a result, it is possible to prevent liquid surface disturbance caused by collision between the liquid refrigerant that flows into the container through the inlet pipe and is reflected by the inner wall surface and the liquid refrigerant stored in the lower part of the container, and it is possible to improve the liquid backflow resistance without providing a partition plate inside the container.

[0010] Fig. 1 is a schematic plan view showing a receiver according to embodiment 1. Fig. 2 is a schematic front view showing a receiver according to embodiment 1. Fig. 3 is a schematic view of a transverse section of a receiver according to embodiment 1 viewed from above. Fig. 4 is a schematic view of a longitudinal section of a receiver according to embodiment 1 viewed from the front. Fig. 5 is a schematic view of a longitudinal section of a receiver according to embodiment 1 viewed from the rear. Fig. 6 is a schematic view of a longitudinal section of a receiver according to embodiment 1 viewed from the side. Fig. 7 is a schematic view showing an example of a refrigeration cycle device equipped with the receiver of Fig. 1. Fig. 8 is a diagram showing the amount of system refrigerant (L) that becomes liquid back for each operating frequency of the compressor.

[0011] Embodiment 1. FIG. 1 is a schematic plan view of a receiver 1 according to Embodiment 1. FIG. 2 is a schematic front view of a receiver 1 according to Embodiment 1. FIG. 3 is a schematic top view of a transverse section of the receiver 1 according to Embodiment 1. FIG. 4 is a schematic front view of a longitudinal section of the receiver 1 according to Embodiment 1. FIG. 5 is a schematic rear view of a longitudinal section of the receiver 1 according to Embodiment 1. FIG. 6 is a schematic side view of a longitudinal section of the receiver 1 according to Embodiment 1. FIG. 7 is a schematic diagram showing an example of a refrigeration cycle apparatus 100 including the receiver 1 of FIG. 1. FIG. 8 is a diagram showing the amount of system refrigerant (L) that becomes liquid back for each operating frequency of the compressor 15. In FIGS. 1 to 6, the arrow X direction represents the width direction of the receiver 1, the arrow Y direction represents the depth direction of the receiver 1, and the arrow Z direction represents the height direction of the receiver 1.

[0012] As shown in Fig. 1, the receiver 1 includes a cylindrical container 1A, and an inlet pipe 1B and an outlet pipe 1C connected to the container 1A. In the example shown in Fig. 1, the container 1A is configured by joining a circular-cylinder body 12 and a circular-cylinder lid 13 to both ends of the body 12. As shown in Fig. 7, the receiver 1 is mounted in a refrigeration cycle apparatus 100, such as an air conditioner, having a refrigerant circuit C1, and stores a refrigerant therein.

[0013] (Refrigeration cycle apparatus 100) The refrigerant circuit C1 is formed by connecting a compressor 15, a first heat exchanger 17, a pressure reducing device 18, a second heat exchanger 19, and a receiver 1, etc., via refrigerant piping. The compressor 15 compresses the refrigerant and circulates it through the refrigerant circuit C1. The first heat exchanger 17 and the second heat exchanger 19 exchange heat between the refrigerant and air. The pressure reducing device 18, which is, for example, an expansion valve, expands and reduces the pressure of the refrigerant. The receiver 1 is provided on the suction side of the compressor 15 and temporarily stores liquid refrigerant that has not been completely evaporated in an evaporator (e.g., the second heat exchanger 19). In the example shown in FIG. 7 , the refrigerant circuit C1 also includes a flow path switching device 16. The flow path switching device 16 switches the flow path of the refrigerant discharged from the compressor 15 and is, for example, a four-way valve.

[0014] 7, the refrigeration cycle apparatus 100 has an outdoor unit 100A installed outdoors and an indoor unit 100B installed indoors, which is a space to be air-conditioned. In the example shown in Fig. 7, the receiver 1, compressor 15, flow path switching device 16, and first heat exchanger 17 are mounted in the outdoor unit 100A, and the pressure reducing device 18 and second heat exchanger 19 are mounted in the indoor unit 100B.

[0015] The flow path switching device 16 switches between cooling and heating. In cooling operation, the refrigerant discharged from the compressor 15 flows through the first heat exchanger 17, the pressure reducing device 18, the second heat exchanger 19, and the receiver 1 in this order, before returning to the compressor 15. On the other hand, in heating operation, the refrigerant discharged from the compressor 15 flows through the second heat exchanger 19, the pressure reducing device 18, the first heat exchanger 17, and the receiver 1 in this order, before returning to the compressor 15. That is, during room cooling, the first heat exchanger 17 functions as a condenser, and the second heat exchanger 19 functions as an evaporator, and during room heating, the second heat exchanger 19 functions as a condenser, and the first heat exchanger 17 functions as an evaporator.

[0016] The receiver 1 is disposed in the housing (not shown) of the outdoor unit 100A so that the ridge of the cylindrical container center portion 1A1 (see FIG. 1) faces downward. Specifically, the receiver 1 is placed horizontally so that the axis Ax (see FIG. 1) of the container center portion 1A1 extends in a generally horizontal direction. The inlet pipe 1B of the receiver 1 is connected to the outlet side of the evaporator, and the outlet pipe 1C of the receiver 1 is connected to the suction side of the compressor 15. The receiver 1 has the functions of storing excess refrigerant during operation, adjusting the amount of liquid refrigerant flowing into the compressor 15 so that the liquid return rate is below a limit value, and returning refrigeration oil discharged from the compressor 15 together with the refrigerant to the compressor 15 without allowing it to remain in the container 1A.

[0017] The refrigeration cycle apparatus 100 to which the receiver 1 is applied is not limited to an air conditioner. The receiver 1 can be applied to refrigeration cycle apparatuses 100 such as refrigerators, freezers, vending machines, refrigeration systems, and water heaters. The configuration of the refrigerant circuit C1 of the refrigeration cycle apparatus 100 is not limited to the above configuration. For example, the flow path switching device 16 can be omitted. Furthermore, for example, the receiver 1 can be disposed at a position in the refrigerant circuit C1 where a medium-pressure refrigerant flows. In this case, the receiver 1 temporarily stores the refrigerant flowing out of the condenser or the refrigerant flowing out of the evaporator.

[0018] Below, with reference to Figures 1 to 6, the container 1A is divided into multiple sections based on its shape, and the arrangement of the inlet pipe 1B and the outlet pipe 1C in the container 1A will be described. Note that the form of the drawings shown below is not intended to limit the present disclosure. The dimensional relationships between components in the following drawings, including Figure 1, may differ from those in reality. Furthermore, in each drawing, identical reference numerals denote identical or equivalent components, and this applies throughout the entire specification. In the following description, directional terms (e.g., "up," "down," "right," "left," "front," and "rear") are used as appropriate to facilitate understanding. However, these terms are for explanatory purposes and do not limit the present disclosure. Unless otherwise specified, these directional terms refer to the direction of the receiver 1 as viewed from the front (front side) when the receiver 1 is positioned so that the axial direction of the axis Ax of the container 1A is horizontal (the direction of arrow X), i.e., so that the axis Ax is perpendicular to the direction of gravity.

[0019] (Container 1A) The container 1A has a cylindrical container center portion 1A1 and a first container end portion 1A31 and a second container end portion 1A32, each of which has a curved, outwardly convex shape and is provided on both sides of the container center portion 1A1 in the axial direction (arrow X direction). The first container end portion 1A31 is located to the left of the container center portion 1A1, and the second container end portion 1A32 is located to the right of the container center portion 1A1. In the example shown in FIG. 1, the container center portion 1A1 is cylindrical, and the first container end portion 1A31 and the second container end portion 1A32 are each hemispherical. In addition, in the example shown in FIG. 1, in a plan view of the receiver 1, the container center portion 1A1 is rectangular, and the first container end portion 1A31 and the second container end portion 1A32 are each semicircular. Furthermore, the container 1A is shaped so that its width in the axial direction (arrow X direction) is greater than its width in the depth direction (arrow Y direction).

[0020] The shape of the container 1A is not limited to the above. The cross section of the container 1A perpendicular to the axis Ax may be, for example, an ellipse, a polygon, or a shape that combines straight lines and curves.

[0021] 6, the container central portion 1A1 can be divided into four regions in the circumferential direction: a top surface portion 1A12, a bottom surface portion 1A11, and two side surface portions 1A13 and 1A14 connecting the top surface portion 1A12 and the bottom surface portion 1A11. In the depth direction of the container 1A (the direction of the arrow Y), the side surface portion 1A13 forms the front surface of the container central portion 1A1, and the side surface portion 1A14 forms the back surface of the container central portion 1A1.

[0022] As shown in Figures 4 and 5, the inlet pipe 1B and the outlet pipe 1C are installed so as to penetrate the upper surface 1A12 of the container central portion 1A1. Specifically, the outer periphery of a portion of the inlet pipe 1B and the outer periphery of a portion of the outlet pipe 1C are connected to the upper surface 1A12, respectively, and the ends 1BE and 1CE formed by the openings of the inlet pipe 1B and the outlet pipe 1C are located in the space within the container 1A. The maximum amount of liquid refrigerant that can be stored in the receiver 1 is determined by the height position of the end 1CE of the outlet pipe 1C. In the example shown in Figures 4 and 5, in order to maximize the maximum amount that can be stored, the end 1CE of the outlet pipe 1C is located near the upper surface 1A12 of the container central portion 1A1. It is also desirable that the end 1BE of the inlet pipe 1B be located at an upper portion within the container 1A.

[0023] The inlet pipe 1B and the outlet pipe 1C may be installed at any location on the container 1A, and for example, the inlet pipe 1B may be installed at the first container end 1A31 of the container 1A, and the outlet pipe 1C may be installed at the container center 1A1 of the container 1A. However, as shown in Figures 4 and 5, when the inlet pipe 1B is installed at the top surface 1A12 of the container 1A, the inlet pipe 1B is less likely to be immersed in the liquid refrigerant stored in the container 1A than when the inlet pipe 1B is installed at another location.

[0024] 1, the inlet pipe 1B and the outlet pipe 1C are arranged on the upper surface 1A12 of the container 1A so that a line (not shown) connecting the centers of the connection portion between the container 1A and the inlet pipe 1B and the connection portion between the container 1A and the outlet pipe 1C is parallel to the axis Ax of the container 1A. Note that the positional relationship between the connection portion between the inlet pipe 1B and the connection portion between the outlet pipe 1C in the container 1A does not need to be the positional relationship described above.

[0025] 4 and 5, the container center portion 1A1 can be divided into three equal parts in the axial direction (direction of arrow X). Hereinafter, the three equal parts obtained by dividing the container center portion 1A1 into three equal parts in the axial direction will be referred to as the first cylindrical portion 1A1A, the second cylindrical portion 1A1B, and the third cylindrical portion 1A1C, starting from the left side, i.e., the first container end portion 1A31. In addition, within the space within the container 1A, the region surrounded by the second cylindrical portion 1A1B will be referred to as the central region RB, the space to the left of the central region RB will be referred to as the first region RA, and the space to the right of the central region RB will be referred to as the second region RC. That is, the space within the container 1A is divided into a first region RA surrounded by the first container end 1A31 and the first cylindrical portion 1A1A, a central region RB surrounded by the second cylindrical portion 1A1B, and a second region RC surrounded by the third cylindrical portion 1A1C and the second container end 1A32.

[0026] (Inlet piping 1B) In the example shown in Figures 4 and 5, the inlet piping 1B has an approximately L-shape when viewed from behind, and has a straight section 1B1 that extends in an approximately straight line from the other end outside the container 1A to the connection part with the container 1A, and a bent section 1B2 that is bent from the connection part with the container 1A to one end 1BE inside the container 1A.

[0027] The other end of the straight section 1B1, i.e., the other end of the inlet pipe 1B, is connected to the outlet side of the evaporator in the refrigerant circuit C1 (see FIG. 7), and one end of the straight section 1B1 is connected to the other end of the bent section 1B2, so that they communicate with each other. In other words, the components of the refrigerant circuit C1 outside the container 1A are connected to the bent section 1B2 of the inlet pipe 1B inside the container 1A via the straight section 1B1 of the inlet pipe 1B.

[0028] One end of the bent portion 1B2 is the end 1BE of the inlet pipe 1B described above and is formed with an opening. In the example shown in Figures 4 and 5, the entire bent portion 1B2 is curved in an arc shape, and one end of the bent portion 1B2 has an end surface inclined with respect to the pipe axis CA1 on the one end side of the bent portion 1B2. In other words, the one end 1BE of the inlet pipe 1B is notched obliquely, rather than perpendicularly, to the pipe axis CA1 on the one end side of the bent portion 1B2. Note that the pipe axis CA1 is the central axis of the pipe on the one end side of the bent portion 1B2. The inlet pipe 1B is installed on the upper surface portion 1A12 of the container 1A, and the one end 1BE of the bent portion 1B2 faces the first container end portion 1A31. In this way, the one end 1BE of the inlet pipe 1B is formed so as to be inclined with respect to the pipe axis CA1 on one end side of the bent portion 1B2, so that the cross-sectional area of ​​the one end 1BE of the inlet pipe 1B can be made larger than when the one end 1BE of the inlet pipe 1B is formed perpendicular to the pipe axis CA1 on one end side of the bent portion 1B2. As a result, the liquid refrigerant flowing into the container 1A via the inlet pipe 1B can be decelerated. Furthermore, by decelerating the liquid refrigerant flowing into the container 1A, it is possible to suppress disturbance of the liquid surface caused by collision between the liquid refrigerant that has flowed into the container 1A and reflected off the inner wall surface and the liquid refrigerant stored in the container 1A. As a result, the liquid refrigerant is further prevented from flowing into the opening of the one end 1CE of the outlet pipe 1C.

[0029] The radius of curvature of the bent portion 1B2 is greater than 90°. This means that the angle θ1 between the pipe axis CA1 at one end of the bent portion 1B2 and the pipe axis CA2 at the other end of the bent portion 1B2 is greater than 90°. The pipe axis CA2 is the central axis of the pipe at the other end of the bent portion 1B2. If the radius of curvature of the bent portion 1B2 is small (i.e., 90° or less), a larger centrifugal force is applied to the liquid refrigerant due to the smaller radius, which tends to cause the refrigerant with high kinetic energy to be concentrated at the bottom of the inlet pipe 1B. When the liquid refrigerant flows into the receiver 1 in this state, the liquid refrigerant with high kinetic energy reflected by the inner wall surface collides with the liquid refrigerant stored in the lower part of the container 1A, causing a disturbance in the liquid surface. Therefore, by making the R of the bent portion 1B2 greater than 90°, centrifugal force is less likely to be applied to the liquid refrigerant than when the R of the bent portion 1B2 is less than 90°, making it less likely that the liquid refrigerant will be biased toward the lower side of the inlet pipe 1B, thereby preventing the liquid refrigerant with high kinetic energy from biasing toward the lower side of the inlet pipe. As a result, it is possible to prevent the liquid surface from being disturbed by collision between the liquid refrigerant that flows into the container 1A through the inlet pipe 1B and is reflected by the inner wall surface and the liquid refrigerant stored in the lower part of the container 1A.

[0030] The shape of the bent portion 1B2 is not limited to the above-described shape, and for example, only a portion of the bent portion 1B2 may be curved. More specifically, the straight portion 1B1 side of the bent portion 1B2 may be straight, and the one end 1BE side of the bent portion 1B2 may be curved. The shape of the bent portion 1B2 may be determined appropriately depending on the positional relationship between the connection portion of the inlet pipe 1B with the container 1A and the one end 1BE of the inlet pipe 1B, etc.

[0031] As shown in Figures 4 and 5, one end 1BE of the inlet pipe 1B is positioned so as to be located in a first region RA of the space within the container 1A. In the example shown in Figures 4 and 5, the entire bent portion 1B2 of the inlet pipe 1B located within the container 1A and the connection portion of the inlet pipe 1B with the container 1A are depicted as being located in the first region RA. In the example shown in Figures 4 and 5, the connection portion of the inlet pipe 1B with the container 1A is also located in the first region RA.

[0032] It is sufficient that one end 1BE of the inlet pipe 1B is located in the first region RA, and for example, the connection portion of the inlet pipe 1B with the container 1A and part of the bent portion 1B2 may be located in the central region RB or the second region RC. Also, for example, the connection portion of the inlet pipe 1B with the container 1A may be located in the central region RB or the second region RC.

[0033] As shown in FIG. 3, one end 1BE of the inlet pipe 1B is located in the first area RA, and an extension line L1 of the central axis of the opening of the one end 1BE of the inlet pipe 1B to the outside of the pipe intersects with the inner wall surface of the container 1A that faces the first area RA.

[0034] The central axis of the opening of one end 1BE of the inlet pipe 1B passes through the center of the opening of one end 1BE of the inlet pipe 1B and is an axis extending perpendicular to the one end 1BE, and is different from the pipe axis CA1 on one end side of the bent portion 1B2 which extends in an inclined direction relative to the one end 1BE of the inlet pipe 1B.

[0035] By specifying the position of one end 1BE of the inlet pipe 1B in the container 1A and the direction of the extension line L1 of the central axis of the opening of the one end 1BE to the outside of the pipe as described above, it is possible to suppress disturbance of the liquid surface caused by collision between the liquid refrigerant that flows into the container 1A via the inlet pipe 1B and is reflected by the inner wall surface and the liquid refrigerant stored in the lower part of the container 1A, compared to a case where the above conditions are not satisfied, for example, where the extension line L1 of the central axis of the opening of the one end 1BE to the outside of the pipe intersects with the inner wall surface of the container 1A facing the second region RC.

[0036] 3, one end 1BE of inlet pipe 1B is disposed so that, in a plan view, an extension line L1 of the central axis of the opening of one end 1BE of inlet pipe 1B to the outside of the pipe is located within a range of 230° to 310° counterclockwise (arrow CC in FIG. 3) from an extension line L2 extending from one end 1BE of inlet pipe 1B directly in front of container 1A. In other words, the angle formed by the extension line L2 extending from one end 1BE of inlet pipe 1B to the directly front of container 1A and the extension line L1 of the central axis of the opening of one end 1BE of inlet pipe 1B to the outside of the pipe (hereinafter referred to as the inlet pipe rotation angle) is within a range of 230° to 310° counterclockwise from extension line L2. This is the range of inlet pipe rotation angles that can improve liquid backflow resistance, and is based on the results of actual equipment tests and analyses described below.

[0037] First, an actual machine test was conducted, and the results shown in Figure 8 were obtained. Figure 8 is a graph showing the amount of system refrigerant (L) that liquid-backed at each operating frequency of the compressor 15. The vertical axis of Figure 8 represents the amount of system refrigerant (L) that liquid-backed, with the amount of system refrigerant (L) that liquid-backed decreasing toward the bottom and increasing toward the top. Therefore, in Figure 8, the amount of system refrigerant (L) that liquid-backed is greater at the top. The greater the amount of system refrigerant (L) that liquid-backed, the greater the storage capacity and the better the liquid-back resistance. The actual machine test results shown in Figure 8 revealed that, at each operating frequency of the compressor 15, an inlet pipe rotation angle of 270° provided the best liquid-back resistance.

[0038] Next, an analysis was performed at operating frequencies of the compressor 15 of 75 (rps) and 125 (rps), and the slope of the approximation curve (= liquid back increase rate (kg / s)) at each inlet pipe rotation angle was calculated. The analysis results are shown in Tables 1 and 2. This analysis result also showed that an inlet pipe rotation angle of 270° provided the best liquid backflow resistance.

[0039]

[0040]

[0041] As described above, the results of the actual machine tests and the analysis show that an inlet pipe rotation angle of 270° provides the best resistance to liquid backflow, and that resistance to liquid backflow is also good within a range around this angle (plus or minus). Therefore, by setting the allowable value for resistance to liquid backflow within a range of plus or minus 40° and setting the inlet pipe rotation angle within a range of plus or minus 40° of 270°, that is, within a range of 230° to 310°, it is possible to improve resistance to liquid backflow.

[0042] In order to suppress disturbance of the liquid level of the liquid refrigerant stored in the lower part of the container 1A, one end 1BE of the inlet pipe 1B is provided at a certain distance or more from the bottom surface 1A11 in the height direction (arrow Z direction) of the container 1A, as shown in Figures 4 and 5. Specifically, if the height of the liquid level when the container 1A stores a predetermined maximum amount of liquid refrigerant that can be stored in the receiver 1 is defined as a reference position, the one end 1BE of the inlet pipe 1B is located above the reference position. In the example shown in Figure 2, the one end 1BE of the inlet pipe 1B is located above the axis Ax and below the one end 1CE of the outlet pipe 1C in the height direction (arrow Z direction) of the container 1A.

[0043] The shape of the inlet pipe 1B is not limited to the shape shown in Figures 4 and 5. The entire inlet pipe 1B may be linear as long as one end 1BE of the inlet pipe 1B, which is formed with an opening, is located in the first region RA and the extension line L1 intersects with a portion of the inner wall surface that faces the first region RA.

[0044] 4 and 5, the outlet piping 1C has a U-shape in front view, and includes a first piping section 1C1 and a second piping section 1C3 that are linear and extend in the vertical direction (direction of arrow Z), and a U-shaped bent section 1C2 that connects the first piping section 1C1 and the second piping section 1C3. In the outlet piping 1C, a portion of the first piping section 1C1 is disposed outside the container 1A, and the other portion is disposed inside the container 1A.

[0045] 4 and 5, the other end of the first piping section 1C1, i.e., the other end of the outlet piping 1C, is connected to the suction side of the compressor 15 in the refrigerant circuit C1 (see FIG. 7), and one end of the first piping section 1C1 is connected to and communicates with the other end of the bent section 1C2. One end of the bent section 1C2 is connected to and communicates with the other end of the second piping section 1C3. In other words, the components of the refrigerant circuit C1 outside the container 1A are connected to the bent section 1C2 and the second piping section 1C3 in the outlet piping 1C within the container 1A via the first piping section 1C1 of the outlet piping 1C.

[0046] A hole 1C4 for returning refrigeration oil to the compressor 15 is formed in the portion of the first piping section 1C1 located within the container 1A. A straw tube 1D having an inverted L-shape in front view is connected to the hole 1C4. In other words, the outlet piping 1C has a straw tube 1D branching off from the other end of the piping and extending downward. The straw tube 1D has a linear first piping section 1D1 extending horizontally (in the direction of arrow X) and a linear second piping section 1D2 extending vertically (in the direction of arrow Z). The diameter of the straw tube 1D is smaller than the diameter of the outlet piping 1C. The other end of the first piping section 1D1, i.e., the other end of the straw tube 1D, is connected to the hole 1C4 of the first piping section 1C1, and one end of the first piping section 1D1 is connected to the other end of the second piping section 1D2. Furthermore, one end 1DE of the second piping section 1D2, i.e., one end 1DE of the straw tube 1D, is formed with an opening and is located at approximately the same height as the bent section 1C2. The straw tube 1D allows refrigeration oil that flows out from the compressor 15 together with the refrigerant to be returned to the compressor 15 without accumulating in the receiver 1. Note that by configuring the second piping section 1D2 to extend downward from one end of the first piping section 1D1, it is possible to avoid a situation in which refrigeration oil is likely to stagnate in the first piping section 1D1, which occurs when the second piping section 1D2 is configured to extend upward from one end of the first piping section 1D1.

[0047] 5, an oil return hole 1C5 for returning refrigerating machine oil to the compressor 15 is formed in the bent portion 1C2 on the side of the bottom surface 1A11 of the container 1A. The oil return hole 1C5 allows refrigerating machine oil that flows out from the compressor 15 together with the refrigerant to be returned to the compressor 15 without being retained in the receiver 1. The shape of the bent portion 1C2 is not limited to a U-shape, and may be, for example, a shape parallel to the bottom surface 1A11 of the container 1A.

[0048] One end of the second piping section 1C3 is the end 1CE of the outlet piping 1C described above, and is formed with an opening. In the example shown in Figures 4 and 5, the one end of the second piping section 1C3, i.e., the end 1CE of the outlet piping 1C, is located in the central region RB of the space within the container 1A.

[0049] The shape of the outlet pipe 1C is not limited to the above-described shape. For example, the entire outlet pipe 1C may be linear as long as one end 1CE of the outlet pipe 1C is located inside the container 1A. Furthermore, two or more outlet pipes 1C may be provided in the container 1A. In this case, the shape of the outlet pipe 1C and the height position of one end 1CE may be configured differently for each outlet pipe 1C.

[0050] Furthermore, one end 1CE of the outlet pipe 1C has an end surface inclined relative to the pipe axis CA3 of one end of the second pipe section 1C3. In other words, one end 1CE of the outlet pipe 1C is notched obliquely, rather than perpendicularly, to the pipe axis CA3 of one end of the second pipe section 1C3. The pipe axis CA3 is the central axis of the pipe of one end of the second pipe section 1C3. Because one end 1CE of the outlet pipe 1C is inclined relative to the pipe axis CA3 of one end of the second pipe section 1C3, the cross-sectional area of ​​the one end 1CE of the outlet pipe 1C can be increased compared to when the one end 1CE is formed perpendicular to the pipe axis CA3 of one end of the second pipe section 1C3. As a result, pressure loss due to contraction can be reduced. Here, contraction occurs when a fluid flows from a large space such as the container 1A into a small space such as the outlet pipe 1C, which increases pressure loss. Therefore, it is preferable to have a small difference between the large space and the small space. Therefore, by increasing the cross-sectional area of ​​one end 1CE of the outlet pipe 1C, the difference between the large space and the small space can be reduced, and the influence of pressure loss due to contraction can be suppressed.

[0051] As shown in Figures 4 and 5, a step ST is formed on the inner wall of the top surface 1A12 of the container center portion 1A1 on the first container end 1A31 side, i.e., the inner wall of the top surface 1A12 of the first cylindrical portion 1A1A of the container center portion 1A1. This step ST is higher on the left side, i.e., the first container end 1A31 side, and lower on the right side, i.e., the second container end 1A32 side. This step ST blocks liquid refrigerant that flows into the container 1A via the inlet pipe 1B, reflects off the inner wall surface of the container 1A opposite the one end 1BE, and spreads toward the one end 1CE of the outlet pipe 1C. As a result, liquid refrigerant is prevented from flowing into the opening of the one end 1CE of the outlet pipe 1C.

[0052] As described above, the receiver 1 according to embodiment 1 has a cylindrical central container portion 1A1, a first container end portion 1A31 and a second container end portion 1A32 which are curved and convex outward and are provided on both sides of the central container portion 1A1 in the axial direction, and is equipped with a horizontally placed container 1A for storing a refrigerant, and an outlet pipe 1C and an inlet pipe 1B which are installed in the container 1A and have one end formed as an opening and are positioned within the container 1A. The space within the container 1A has a central region RB surrounded by a central cylindrical portion (second cylindrical portion 1A1B) that divides the container central portion 1A1 into three equal parts in the axial direction, a first region RA that is closer to the first container end 1A31 than the central region RB, and a second region RC that is closer to the second container end 1A32 than the central region RB. The other end of the outlet pipe 1C is arranged to be located above the second region RC. The inlet pipe 1B is arranged so that one end 1BE of the inlet pipe 1B is located in the first region RA and so that an extension line L1 of the central axis of the opening of the one end 1BE to the outside of the pipe intersects with a portion of the inner wall surface of the container 1A that faces the first region RA. The inlet pipe 1B has a bent portion 1B2 that is bent from the connection portion with the container 1A to one end side within the container 1A, and the angle θ1 between the tube axis CA1 on one end side of the bent portion 1B2 and the tube axis CA2 on the other end side is greater than 90°.

[0053] According to the receiver 1 of the first embodiment, the inlet pipe 1B has one end 1BE located in the first region RA, an extension line L1 of the central axis of the opening of the inlet pipe 1B to the outside of the pipe intersects with a portion of the inner wall surface of the container 1A facing the first region RA, and a bent portion 1B2 is formed from the connection portion with the container 1A to one end inside the container 1A, and the angle θ1 between the pipe axis CA1 at one end of the bent portion 1B2 and the pipe axis CA2 at the other end is greater than 90°. This configuration reduces the application of centrifugal force to the liquid refrigerant passing through the inlet pipe 1B, thereby preventing liquid refrigerant with high kinetic energy from being concentrated toward the lower part of the inlet pipe. As a result, liquid level disturbance caused by collision between the liquid refrigerant flowing into the container 1A through the inlet pipe 1B and reflected by the inner wall surface and the liquid refrigerant stored in the lower part of the container 1A is reduced, thereby improving the liquid backflow resistance without providing a partition plate inside the container 1A.

[0054] In the receiver 1 according to the first embodiment, the one end 1BE of the inlet pipe 1B is formed so as to be inclined with respect to the pipe axis CA1 on the one end 1BE side.

[0055] According to the receiver 1 of the first embodiment, the one end 1BE of the inlet pipe 1B is inclined with respect to the pipe axis CA1 on the one end 1BE side. This allows the cross-sectional area of ​​the one end 1BE of the inlet pipe 1B to be larger than when the one end 1BE is formed perpendicular to the pipe axis CA1 on the one end 1BE side. As a result, the liquid refrigerant flowing into the container 1A via the inlet pipe 1B can be decelerated. Furthermore, by decelerating the liquid refrigerant flowing into the container 1A, disturbance of the liquid surface due to collision between the liquid refrigerant that has entered the container 1A and reflected off the inner wall surface and the liquid refrigerant stored in the container 1A can be suppressed. As a result, the liquid refrigerant is further prevented from flowing into the opening of the one end 1CE of the outlet pipe 1C.

[0056] In the receiver 1 according to the first embodiment, the one end 1CE of the outlet pipe 1C is formed so as to be inclined with respect to the pipe axis CA3 on the one end 1CE side.

[0057] According to the receiver 1 of the first embodiment, the one end 1CE of the outlet pipe 1C is formed so as to be inclined with respect to the pipe axis CA3 on the one end 1CE side, which makes it possible to increase the cross-sectional area of ​​the one end 1CE of the outlet pipe 1C compared to when the one end 1CE is formed perpendicular to the pipe axis CA3 on the one end 1CE side. As a result, it is possible to reduce pressure loss due to contraction of the flow that occurs when a fluid flows from a large space to a small space.

[0058] In the receiver 1 according to the first embodiment, the outlet pipe 1C has a straw tube 1D that branches off from the other end of the pipe and extends downward.

[0059] According to the receiver 1 of the first embodiment, the straw tube 1D allows the refrigeration oil that flows out from the compressor 15 together with the refrigerant to be returned to the compressor 15 without being retained in the receiver 1.

[0060] In addition, in the receiver 1 of embodiment 1, a step ST is formed on the inner wall of the upper surface portion 1A12 of the container center portion 1A1 on the first container end portion 1A31 side, and the step ST is higher on the first container end portion 1A31 side and lower on the second container end portion 1A32 side.

[0061] According to the receiver 1 of the first embodiment, the step ST can block the liquid refrigerant that flows into the container 1A through the inlet pipe 1B, reflects off the inner wall surface of the container 1A facing the end 1BE, and spreads toward the end 1CE of the outlet pipe 1C. As a result, the liquid refrigerant is prevented from flowing into the opening of the end 1CE of the outlet pipe 1C.

[0062] In addition, the refrigeration cycle device 100 according to the first embodiment includes a refrigerant circuit C1 that includes at least a compressor 15, a condenser, a pressure reducing device 18, an evaporator, and the above-mentioned receiver 1, all connected by refrigerant piping.

[0063] According to the refrigeration cycle apparatus 100 of the first embodiment, the same effects as those of the receiver 1 described above can be obtained.

[0064] 1 Receiver, 1A Container, 1A1 Container center, 1A11 Bottom, 1A12 Top, 1A13 Side, 1A14 Side, 1A1A First cylindrical portion, 1A1B Second cylindrical portion, 1A1C Third cylindrical portion, 1A31 First container end, 1A32 Second container end, 1B Inlet piping, 1B1 Straight portion, 1B2 Bent portion, 1BE One end, 1C Outlet piping, 1C1 First piping portion, 1C2 Bent portion, 1C3 Second piping portion, 1C4 Hole, 1C5 Oil return hole, 1CE One end, 1D Straw tube, 1D1 First piping portion, 1D2 Second piping portion, 1DE One end, 12 Body, 13 Lid, 15 Compressor, 16 Flow path switching device, 17 First heat exchanger, 18 Pressure reducing device, 19 Second heat exchanger, 100 refrigeration cycle device, 100A outdoor unit, 100B indoor unit, Ax axis, C1 refrigerant circuit, CA1 pipe axis, CA2 pipe axis, CA3 pipe axis, CC arrow, L1 extension line, L2 extension line, θ1 angle, RA first region, RB central region, RC second region, ST step.

Claims

1. A horizontal container for storing a refrigerant, the container having a cylindrical container center, and first and second container ends provided on either side of the axial direction of the container center, the first and second container ends being curved and convex outward; and an outlet pipe and an inlet pipe installed on the container, one end of which is open and located within the container, the space within the container having a central region surrounded by a central cylindrical portion that divides the container center into thirds in the axial direction, a first region located closer to the first container end than the central region, and a second region located closer to the second container end than the central region, the other end of the outlet pipe being provided to be located above the second region, and the inlet pipe is a receiver, wherein one end of the inlet pipe is located in the first region, and an extension line of the central axis of the opening of the one end to the outside of the pipe intersects with a portion of the inner wall surface of the container facing the first region, and the receiver has a bent portion bent from the connection portion with the container to one end side inside the container, and the angle between the pipe axis on one end side of the bent portion and the pipe axis on the other end side is greater than 90°.

2. The receiver according to claim 1, wherein the one end of the inlet pipe is formed so as to be inclined with respect to the pipe axis on the one end side.

3. A receiver as claimed in claim 1 or 2, wherein said one end of said outlet pipe is formed so as to be inclined with respect to the pipe axis on said one end side.

4. A receiver as claimed in any one of claims 1 to 3, wherein the outlet pipe has a straw tube branching off from the other end of the pipe and extending downward.

5. A receiver as described in any one of claims 1 to 4, wherein a step is formed on the inner wall of the upper surface portion of the central part of the container on the side of the first container end, and the step is higher on the side of the first container end and lower on the side of the second container end.

6. A refrigeration cycle device comprising a refrigerant circuit comprising at least a compressor, a condenser, a pressure reducing device, an evaporator, and the receiver according to any one of claims 1 to 5, connected by refrigerant piping.

7. A refrigeration cycle apparatus as described in claim 6, wherein the receiver is disposed on the suction side of the compressor in the refrigerant circuit and temporarily stores the refrigerant flowing out of the evaporator, or is disposed at a position in the refrigerant circuit where medium-pressure refrigerant flows through and temporarily stores the refrigerant flowing out of the condenser or the refrigerant flowing out of the evaporator.

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